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Sample records for auditory color constancy

  1. Color Constancy by Deep Learning

    NARCIS (Netherlands)

    Z. Lou; T. Gevers; N. Hu; M.P. Lucassen

    2015-01-01

    Computational color constancy aims to estimate the color of the light source. The performance of many vision tasks, such as object detection and scene understanding, may benefit from color constancy by estimating the correct object colors. Since traditional color constancy methods are based on speci

  2. Static Filtered Sky Color Constancy

    Directory of Open Access Journals (Sweden)

    Ali Alkhalifah

    2016-05-01

    Full Text Available In Computer Vision, the sky color is used for lighting correction, image color enhancement, horizon alignment, image indexing, and outdoor image classification and in many other applications. In this article, for robust color based sky segmentation and detection, usage of lighting correction for sky color detection is investigated. As such, the impact of color constancy on sky color detection algorithms is evaluated and investigated. The color correction (constancy algorithms used includes Gray-Edge (GE, Gray-World (GW, Max-RGB (MRGB and Shades-of-Gray (SG. The algorithms GE, GW, MRGB, and SG, are tested on the static filtered sky modeling. The static filter is developed in the LAB color space. This evaluation and analysis is essential for detection scenarios, especially, color based object detection in outdoor scenes. From the results, it is concluded that the color constancy before sky color detection using LAB static filters has the potential of improving sky color detection performance. However, the application of the color constancy can impart adverse effects on the detection results. For images, the color constancy algorithms depict a compact and stable representative of the sky chroma loci, however, the sky color locus might have a shifting and deviation in a particular color representation. Since the sky static filters are using the static chromatic values, different results can be obtained by applying color constancy algorithms on various datasets.

  3. Edge classification for color constancy

    NARCIS (Netherlands)

    A. Gijsenij; T. Gevers; J. van de Weijer

    2008-01-01

    The goal of color constancy is to measure image colors despite differences in the color of the light source. Traditionally, the computational method of obtaining this ability is by using pixel values only. Recently, methods using edges instead of pixel values have been proposed. However, different e

  4. Color constancy in Japanese animation

    Science.gov (United States)

    Ichihara, Yasuyo G.

    2006-01-01

    In this study, we measure the colors used in a Japanese Animations. The result can be seen on CIE-xy color spaces. It clearly shows that the color system is not a natural appearance system but an imagined and artistic appearance system. Color constancy of human vision can tell the difference in skin and hair colors between under moonlight and day light. Human brain generates a match to the memorized color of an object from daylight viewing conditions to the color of the object in different viewing conditions. For example, Japanese people always perceive the color of the Rising Sun in the Japanese flag as red even in a different viewing condition such as under moonlight. Color images captured by a camera cannot present those human perceptions. However, Japanese colorists in Animation succeeded in painting the effects of color constancy not only under moonlight but also added the memory matching colors. They aim to create a greater impact on viewer's perceptions by using the effect of the memory matching colors. In this paper, we propose the Imagined Japanese Animation Color System. This system in art is currently a subject of research in Japan. Its importance is that it could also provide an explanation on how human brain perceives the same color under different viewing conditions.

  5. A Physical Basis for Color Constancy

    NARCIS (Netherlands)

    J.M. Geusebroek; R. van den Boomgaard; A.W.M. Smeulders; Th. Gevers

    2002-01-01

    A fundamental problem in psycophysical experiments is that significant conclusions are hard to draw due to the complex experimental environment necessary to examine color constancy. An alternative approach to reveal the mechanisms involved in color constancy is by modeling the physical basis for col

  6. Color constancy by characterization of illumination chromaticity

    Science.gov (United States)

    Nikkanen, Jarno T.

    2011-05-01

    Computational color constancy algorithms play a key role in achieving desired color reproduction in digital cameras. Failure to estimate illumination chromaticity correctly will result in invalid overall colour cast in the image that will be easily detected by human observers. A new algorithm is presented for computational color constancy. Low computational complexity and low memory requirement make the algorithm suitable for resource-limited camera devices, such as consumer digital cameras and camera phones. Operation of the algorithm relies on characterization of the range of possible illumination chromaticities in terms of camera sensor response. The fact that only illumination chromaticity is characterized instead of the full color gamut, for example, increases robustness against variations in sensor characteristics and against failure of diagonal model of illumination change. Multiple databases are used in order to demonstrate the good performance of the algorithm in comparison to the state-of-the-art color constancy algorithms.

  7. Computational color constancy: survey and experiments

    NARCIS (Netherlands)

    A. Gijsenij; T. Gevers; J. van de Weijer

    2011-01-01

    Computational color constancy is a fundamental prerequisite for many computer vision applications. This paper presents a survey of many recent developments and state-of-the-art methods. Several criteria are proposed that are used to assess the approaches. A taxonomy of existing algorithms is propose

  8. Color constancy for multiple light sources

    NARCIS (Netherlands)

    A. Gijsenij; R. Lu; T. Gevers

    2012-01-01

    Color constancy algorithms are generally based on the simplifying assumption that the spectral distribution of a light source is uniform across scenes. However, in reality, this assumption is often violated due to the presence of multiple light sources. In this paper, we will address more realistic

  9. Color constancy enhancement under poor illumination.

    Science.gov (United States)

    Liu, Jun; Shao, Zhenfeng; Cheng, Qimin

    2011-12-15

    In this Letter, the color constancy and its realization were studied and a novel color constancy image enhancement algorithm under poor illumination was presented. The purpose of this algorithm is to maintain the hue of an image during the processing so that the change of saturation can be minimized. The original image was first multiplied by a scale parameter obtained by the adaptive quadratic function to enhance the luminance, and then the edge details were restored by a shifting parameter. Numerical results of the Simon Fraser University (SFU) image database indicated that the proposed algorithm performed much better in preserving the hue and saturation and avoiding color distortion compared with the existing image enhancement algorithms. PMID:22179895

  10. A Color-Opponency Based Biological Model for Color Constancy

    Directory of Open Access Journals (Sweden)

    Yongjie Li

    2011-05-01

    Full Text Available Color constancy is the ability of the human visual system to adaptively correct color-biased scenes under different illuminants. Most of the existing color constancy models are nonphysiologically plausible. Among the limited biological models, the great majority is Retinex and its variations, and only two or three models directly simulate the feature of color-opponency, but only of the very earliest stages of visual pathway, i.e., the single-opponent mechanisms involved at the levels of retinal ganglion cells and lateral geniculate nucleus (LGN neurons. Considering the extensive physiological evidences supporting that both the single-opponent cells in retina and LGN and the double-opponent neurons in primary visual cortex (V1 are the building blocks for color constancy, in this study we construct a color-opponency based color constancy model by simulating the opponent fashions of both the single-opponent and double-opponent cells in a forward manner. As for the spatial structure of the receptive fields (RF, both the classical RF (CRF center and the nonclassical RF (nCRF surround are taken into account for all the cells. The proposed model was tested on several typical image databases commonly used for performance evaluation of color constancy methods, and exciting results were achieved.

  11. Reflectance, illumination, and appearance in color constancy.

    Science.gov (United States)

    McCann, John J; Parraman, Carinna; Rizzi, Alessandro

    2014-01-01

    We studied color constancy using a pair of identical 3-D Color Mondrian displays. We viewed one 3-D Mondrian in nearly uniform illumination, and the other in directional, nonuniform illumination. We used the three dimensional structures to modulate the light falling on the painted surfaces. The 3-D structures in the displays were a matching set of wooden blocks. Across Mondrian displays, each corresponding facet had the same paint on its surface. We used only 6 chromatic, and 5 achromatic paints applied to 104 block facets. The 3-D blocks add shadows and multiple reflections not found in flat Mondrians. Both 3-D Mondrians were viewed simultaneously, side-by-side. We used two techniques to measure correlation of appearance with surface reflectance. First, observers made magnitude estimates of changes in the appearances of identical reflectances. Second, an author painted a watercolor of the 3-D Mondrians. The watercolor's reflectances quantified the changes in appearances. While constancy generalizations about illumination and reflectance hold for flat Mondrians, they do not for 3-D Mondrians. A constant paint does not exhibit perfect color constancy, but rather shows significant shifts in lightness, hue and chroma in response to the structure in the nonuniform illumination. Color appearance depends on the spatial information in both the illumination and the reflectances of objects. The spatial information of the quanta catch from the array of retinal receptors generates sensations that have variable correlation with surface reflectance. Models of appearance in humans need to calculate the departures from perfect constancy measured here. This article provides a dataset of measurements of color appearances for computational models of sensation. PMID:24478738

  12. Reflectance, illumination, and appearance in color constancy

    Directory of Open Access Journals (Sweden)

    John J. McCann

    2014-01-01

    Full Text Available We studied color constancy using a pair of identical 3-D Color Mondrian displays. We viewed one 3-D Mondrian in nearly uniform illumination, and the other in directional, nonuniform illumination. We used the three dimensional structures to modulate the light falling on the painted surfaces. The 3-D structures in the displays were a matching set of wooden blocks. Across Mondrian displays, each corresponding facet had the same paint on its surface. We used only 6 chromatic, and 5 achromatic paints applied to 104 block facets. The 3-D blocks add shadows and multiple reflections not found in flat Mondrians. Both 3-D Mondrians were viewed simultaneously, side-by-side. We used two techniques to measure correlation of appearance with surface reflectance. First, observers made magnitude estimates of changes in the appearances of identical reflectances. Second, an author painted a watercolor of the 3-D Mondrians. The watercolor’s reflectances quantified the changes in appearances. While constancy generalizations about illumination and reflectance hold for flat Mondrians, they do not for 3-D Mondrians. A constant paint does not exhibit perfect color constancy, but rather shows significant shifts in lightness, hue and chroma in response to the structure in the nonuniform illumination. Color appearance depends on the spatial information in both the illumination and the reflectances of objects. The spatial information of the quanta catch from the array of retinal receptors generates sensations that have variable correlation with surface reflectance. Models of appearance in humans need to calculate the departures from perfect constancy measured here. This article provides a dataset of measurements of color appearances for computational models of sensation.

  13. Relational color constancy in achromatic and isoluminant images

    OpenAIRE

    Nascimento, Sérgio M. C.; Foster, David

    2000-01-01

    Relational color constancy, which refers to the constancy of perceived relations between surface colors under changes in illuminant, may be based on the computation of spatial ratios of cone excitations. As this activity need occur only within rather than between cone pathways, relational color constancy might be assumed to be based on relative luminance processing. This hypothesis was tested in a psychophysical experiment in which observers viewed simulated images of Mondrian pat...

  14. Extending "color constancy" outside the visible region.

    Science.gov (United States)

    Ratnasingam, Sivalogeswaran; Collins, Steve; Hernández-Andrés, Javier

    2011-04-01

    In this paper, the results of an investigation of the possibility of extending "color constancy" to obtain illuminant-invariant reflectance features from data in the near-ultraviolet (UV) and near-infrared (IR) wavelength regions are reported. These features are obtained by extending a blackbody-model-based color constancy algorithm proposed by Ratnasingam and Collins [J. Opt. Soc. Am. A27, 286 (2010)] to these additional wavelengths. Ratnasingam and Collins applied the model-based algorithm in the visible region to extract two illuminant-invariant features related to the wavelength-dependent reflectance of a surface from the responses of four sensors. In this paper, this model-based algorithm is extended to extract two illuminant-invariant reflectance features from the responses of sensors that cover the visible and either the near-UV or near-IR wavelength. In this investigation, test reflectance data sets are generated using the goodness-fitness coefficient (GFC). The appropriateness of the GFC for generating the test data sets is demonstrated by comparing the results obtained with these data with those obtained from data sets generated using the CIELab distance. Results based upon the GFC are then presented that suggest that the model-based algorithm can extract useful features from data from the visible and near-IR wavelengths. Finally, results are presented that show that, although the spectrum of daylight in the near UV is very different from a blackbody spectrum, the algorithm can be modified to extract useful features from visible and near-UV wavelengths. PMID:21478947

  15. Evaluating the Limitations of Different Color Constancy Techniques

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    Richa Dogra

    2014-01-01

    Full Text Available This paper presents a review on different color constancy techniques. The color constancy techniques becomes an important pre-processing technique which reduces the effect of the light source on the given image or scene. It is found that light effects lot on a given scene. So effect of the light source may degrades the performance of certain applications a lot like face recognition, object detection, lane detection etc. Color constancy has ability to detection of color independent of light source. It is a characteristic of the distinct color awareness organization which guarantees that the apparent color of objects remains relatively constant under altering illumination conditions. The overall goal of this paper is to evaluate the gaps in existing literature

  16. The nature of instructional effects in color constancy.

    Science.gov (United States)

    Radonjić, Ana; Brainard, David H

    2016-06-01

    The instructions subjects receive can have a large effect on experimentally measured color constancy, but the nature of these effects and how their existence should inform our understanding of color perception remains unclear. We used a factorial design to measure how instructional effects on constancy vary with experimental task and stimulus set. In each of 2 experiments, we employed both a classic adjustment-based asymmetric matching task and a novel color selection task. Four groups of naive subjects were instructed to make adjustments/selections based on (a) color (neutral instructions); (b) the light reaching the eye (physical spectrum instructions); (c) the actual surface reflectance of an object (objective reflectance instructions); or (d) the apparent surface reflectance of an object (apparent reflectance instructions). Across the 2 experiments we varied the naturalness of the stimuli. We find clear interactions between instructions, task, and stimuli. With simplified stimuli (Experiment 1), instructional effects were large and the data revealed 2 instruction-dependent patterns. In 1 (neutral and physical spectrum instructions) constancy was low, intersubject variability was also low, and adjustment-based and selection-based constancy were in agreement. In the other (reflectance instructions) constancy was high, intersubject variability was large, adjustment-based constancy deviated from selection-based constancy and for some subjects selection-based constancy increased across sessions. Similar patterns held for naturalistic stimuli (Experiment 2), although instructional effects were smaller. We interpret these 2 patterns as signatures of distinct task strategies-1 is perceptual, with judgments based primarily on the perceptual representation of color; the other involves explicit instruction-driven reasoning. (PsycINFO Database Record PMID:26727021

  17. Experience-Dependent Color Constancy in Guppies (Poecilia reticulata

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    I. E. Intskirveli

    2002-01-01

    Full Text Available We investigated the ability to recognize the color of surfaces in fish (Poecilia reticulata, bred from birth in conditions of artificial light with constant spectral content. The capacity for color constancy significantly deteriorated when compared that to the control group. Further alteration of lighting conditions and transfer into natural daylight conditions restored the suppressed function to its normal level. We suggest that the color constancy function belongs in the visual system-response functions, the full development of which requires the accumulation of individual visual experience.

  18. Comparing objective and subjective error measures for color constancy

    NARCIS (Netherlands)

    M.P. Lucassen; A. Gijsenij; T. Gevers

    2008-01-01

    We compare an objective and a subjective performance measure for color constancy algorithms. Eight hyper-spectral images were rendered under a neutral reference illuminant and four chromatic illuminants (Red, Green, Yellow, Blue). The scenes rendered under the chromatic illuminants were color correc

  19. A New Color Constancy Model for Machine Vision

    Institute of Scientific and Technical Information of China (English)

    TAO Linmi; XU Guangyou

    2001-01-01

    Both physiological and psychological evidences suggest that the human visual system analyze images in neural subsystems tuned to different attributes of the stimulus. Color module and lightness module are such subsystems. Under this general result, a new physical model of trichromatic system has been developed to deal with the color constancy of computer vision. A normal color image is split into two images: the gray scale image and the equal lightness color image for the two modules. Relatively, a two-dimensional descriptor is applied to describe the property of surface reflectance in the equal lightness color image. This description of surface spectral reflectance has the property of color constancy. Image segmentation experiments based on color property of object show that the presented model is effective.

  20. Exemplar-Based Color Constancy and Multiple Illumination.

    Science.gov (United States)

    Joze, Hamid Reza Vaezi; Drew, Mark S

    2014-05-01

    Exemplar-based learning or, equally, nearest neighbor methods have recently gained interest from researchers in a variety of computer science domains because of the prevalence of large amounts of accessible data and storage capacity. In computer vision, these types of technique have been successful in several problems such as scene recognition, shape matching, image parsing, character recognition, and object detection. Applying the concept of exemplar-based learning to the problem of color constancy seems odd at first glance since, in the first place, similar nearest neighbor images are not usually affected by precisely similar illuminants and, in the second place, gathering a dataset consisting of all possible real-world images, including indoor and outdoor scenes and for all possible illuminant colors and intensities, is indeed impossible. In this paper, we instead focus on surfaces in the image and address the color constancy problem by unsupervised learning of an appropriate model for each training surface in training images. We find nearest neighbor models for each surface in a test image and estimate its illumination based on comparing the statistics of pixels belonging to nearest neighbor surfaces and the target surface. The final illumination estimation results from combining these estimated illuminants over surfaces to generate a unique estimate. We show that it performs very well, for standard datasets, compared to current color constancy algorithms, including when learning based on one image dataset is applied to tests from a different dataset. The proposed method has the advantage of overcoming multi-illuminant situations, which is not possible for most current methods since they assume the color of the illuminant is constant all over the image. We show a technique to overcome the multiple illuminant situation using the proposed method and test our technique on images with two distinct sources of illumination using a multiple-illuminant color constancy

  1. Physics-based edge evaluation for improved color constancy

    NARCIS (Netherlands)

    A. Gijsenij; T. Gevers; J. van de Weijer

    2009-01-01

    Edge-based color constancy makes use of image derivatives to estimate the illuminant. However, different edge types exist in real-world images such as shadow, geometry, material and highlight edges. These different edge types may have a distinctive influence on the performance of the illuminant esti

  2. Color Constancy For Improving Skin Detection

    OpenAIRE

    A. Nadian-Ghomsheh

    2014-01-01

    Skin detection is a preliminary step in many human related recognition systems. Most skin detection systems suffer from high false detection rate, resulting from low variance between the skin and non-skin color distributions. This paper proposes the use of simple color correction algorithms with low computation complexity to obtain a corrected version of the skin color distribution, which could lead to more accurate skin detection. White patch retinex, Grey world assumption and several improv...

  3. A modified image enhancement algorithm based on color constancy

    Institute of Scientific and Technical Information of China (English)

    Cheng Li; Shan Gao; Duyan Bi

    2009-01-01

    According to the color constancy theory,a modified variation Retinex is proposed for improving the visibility of the dark regions in images under insufficient and/or non-uniform lighting conditions.A new penalty functional based on nonlinear diffusion and correlation between the reflectance and the given image is designed for the intensity image enhancement,followed by adaptive color compensation.With high computational efficiency achieved by an improved multi-resolution algorithm,simulation results prove that the proposed method shows more colorful and vivid visual performance,and achieves wider dynamic range with higher objective standard values.

  4. The effect of exposure on MaxRGB color constancy

    Science.gov (United States)

    Funt, Brian; Shi, Lilong

    2010-02-01

    The performance of the MaxRGB illumination-estimation method for color constancy and automatic white balancing has been reported in the literature as being mediocre at best; however, MaxRGB has usually been tested on images of only 8-bits per channel. The question arises as to whether the method itself is inadequate, or rather whether it has simply been tested on data of inadequate dynamic range. To address this question, a database of sets of exposure-bracketed images was created. The image sets include exposures ranging from very underexposed to slightly overexposed. The color of the scene illumination was determined by taking an extra image of the scene containing 4 Gretag Macbeth mini Colorcheckers placed at an angle to one another. MaxRGB was then run on the images of increasing exposure. The results clearly show that its performance drops dramatically when the 14-bit exposure range of the Nikon D700 camera is exceeded, thereby resulting in clipping of high values. For those images exposed such that no clipping occurs, the median error in MaxRGB's estimate of the color of the scene illumination is found to be relatively small.

  5. SIMULTANEOUS COLOR CONSTANCY REVISITED - AN ANALYSIS OF VIEWING STRATEGIES

    NARCIS (Netherlands)

    CORNELISSEN, FW; BRENNER, E

    1995-01-01

    We examined whether matching instructions influenced the eye movements that subjects made during a colour constancy experiment. The instructions changed the average duration of exposure to the spectrally biased surround. We also measured the influence that small changes in exposure duration have on

  6. Orthogonal relations and color constancy in dichromatic colorblindness.

    Directory of Open Access Journals (Sweden)

    Ralph W Pridmore

    Full Text Available This paper employs uniform color space to analyze relations in dichromacy (protanopia, deuteranopia, tritanopia. Fifty percent or less of dichromats represent the classical reduction form of trichromacy, where one of three cones is inoperative but normal trichromatic color mixture such as complementary colors (pairs that mix white are accepted by the dichromat, whose data can thus be plotted to CIE chromaticity spaces. The remaining dichromats comprise many and varied more-complex gene arrays from mutations, recombinations, etc. Though perhaps a minority, the three reductionist types provide a simple standard, in genotype and phenotype, to which the more complex remainder may be compared. Here, previously published data on dichromacy are plotted and analyzed in CIELUV uniform color space to find spatial relations in terms of color appearance space (e.g., hue angle. Traditional residual (seen hues for protanopia and deuteranopia (both red-green colorblindness are yellow and blue, but analysis indicates the protanopic residual hues are more greenish yellow and reddish blue than in tradition. Results for three illuminants (D65, D50, B imply four principles in the spatial structure of dichromacy: (1 complementarity of confusion hue pairs and of residual hue pairs; (2 orthogonality of confusion locus and residual hues locus at their intersection with the white point, in each dichromatic type; (3 orthogonality of protanopic and tritanopic confusion loci; and (4 inverse relations between protanopic and tritanopic systems generally, such that one's confusion hues are the other's residual hues. Two of the three dichromatic systems do not represent components of normal trichromatic vision as sometimes thought but are quite different. Wavelength shifts between illuminants demonstrate chromatic adaptation correlates exactly with that in trichromatic vision. In theory these results clarify relations in and between types of dichromacy. They also apply in

  7. Orthogonal Relations and Color Constancy in Dichromatic Colorblindness

    Science.gov (United States)

    Pridmore, Ralph W.

    2014-01-01

    This paper employs uniform color space to analyze relations in dichromacy (protanopia, deuteranopia, tritanopia). Fifty percent or less of dichromats represent the classical reduction form of trichromacy, where one of three cones is inoperative but normal trichromatic color mixture such as complementary colors (pairs that mix white) are accepted by the dichromat, whose data can thus be plotted to CIE chromaticity spaces. The remaining dichromats comprise many and varied more-complex gene arrays from mutations, recombinations, etc. Though perhaps a minority, the three reductionist types provide a simple standard, in genotype and phenotype, to which the more complex remainder may be compared. Here, previously published data on dichromacy are plotted and analyzed in CIELUV uniform color space to find spatial relations in terms of color appearance space (e.g., hue angle). Traditional residual (seen) hues for protanopia and deuteranopia (both red–green colorblindness) are yellow and blue, but analysis indicates the protanopic residual hues are more greenish yellow and reddish blue than in tradition. Results for three illuminants (D65, D50, B) imply four principles in the spatial structure of dichromacy: (1) complementarity of confusion hue pairs and of residual hue pairs; (2) orthogonality of confusion locus and residual hues locus at their intersection with the white point, in each dichromatic type; (3) orthogonality of protanopic and tritanopic confusion loci; and (4) inverse relations between protanopic and tritanopic systems generally, such that one's confusion hues are the other's residual hues. Two of the three dichromatic systems do not represent components of normal trichromatic vision as sometimes thought but are quite different. Wavelength shifts between illuminants demonstrate chromatic adaptation correlates exactly with that in trichromatic vision. In theory these results clarify relations in and between types of dichromacy. They also apply in Munsell and

  8. Accurate moving cast shadow suppression based on local color constancy detection.

    Science.gov (United States)

    Amato, Ariel; Mozerov, Mikhail G; Bagdanov, Andrew D; Gonzàlez, Jordi

    2011-10-01

    This paper describes a novel framework for detection and suppression of properly shadowed regions for most possible scenarios occurring in real video sequences. Our approach requires no prior knowledge about the scene, nor is it restricted to specific scene structures. Furthermore, the technique can detect both achromatic and chromatic shadows even in the presence of camouflage that occurs when foreground regions are very similar in color to shadowed regions. The method exploits local color constancy properties due to reflectance suppression over shadowed regions. To detect shadowed regions in a scene, the values of the background image are divided by values of the current frame in the RGB color space. We show how this luminance ratio can be used to identify segments with low gradient constancy, which in turn distinguish shadows from foreground. Experimental results on a collection of publicly available datasets illustrate the superior performance of our method compared with the most sophisticated, state-of-the-art shadow detection algorithms. These results show that our approach is robust and accurate over a broad range of shadow types and challenging video conditions. PMID:21435975

  9. Constancy of target velocity as a critical factor in the emergence of auditory and visual representational momentum.

    Science.gov (United States)

    Getzmann, Stephan; Lewald, Jörg

    2009-03-01

    Representational momentum refers to the tendency to displace the judged final position of a moving auditory or visual target as being too far forward along the path of motion. This phenomenon was investigated here by comparing apparent displacements in final position with constant or with irregularly varying target velocities. Final positions of auditory or visual targets, moving along the horizontal plane, were indicated by manual pointing. In both modalities, we found a significantly smaller displacement magnitude with varying velocities compared to constant velocity. The reduction in displacement occurred irrespective of whether or not the participants pursued the visual targets with their eyes. These findings indicate that the emergence of representational momentum critically depends on the constancy of target velocity. The results are compatible with a model in which changes in the motion signal can override the extrapolation mechanism that usually causes the forward displacement of representational momentum.

  10. Across frequency processes involved in auditory detection of coloration

    DEFF Research Database (Denmark)

    Buchholz, Jörg; Kerketsos, P

    2008-01-01

    When an early wall reflection is added to a direct sound, a spectral modulation is introduced to the signal's power spectrum. This spectral modulation typically produces an auditory sensation of coloration or pitch. Throughout this study, auditory spectral-integration effects involved in coloration...... detection are investigated. Coloration detection thresholds were therefore measured as a function of reflection delay and stimulus bandwidth. In order to investigate the involved auditory mechanisms, an auditory model was employed that was conceptually similar to the peripheral weighting model [Yost, JASA...... filterbank was designed to approximate auditory filter-shapes measured by Oxenham and Shera [JARO, 2003, 541-554], derived from forward masking data. The results of the present study demonstrate that a “purely” spectrum-based model approach can successfully describe auditory coloration detection even at high...

  11. Investigation of Color Constancy in 4.5-Month-Old Infants under a Strict Control of Luminance Contrast for Individual Participants

    Science.gov (United States)

    Yang, Jiale; Kanazawa, So; Yamaguchi, Masami K.; Kuriki, Ichiro

    2013-01-01

    The current study examined color constancy in infants using a familiarization paradigm. We first obtained isoluminance in each infant as defined by the minimum motion paradigm and used these data to control the luminance of stimuli in the main experiments. In the familiarization phase of the main experiment, two identical smiling face patterns…

  12. The Application of Support Vector Machine (svm) Using Cielab Color Model, Color Intensity and Color Constancy as Features for Ortho Image Classification of Benthic Habitats in Hinatuan, Surigao del Sur, Philippines

    Science.gov (United States)

    Cubillas, J. E.; Japitana, M.

    2016-06-01

    This study demonstrates the application of CIELAB, Color intensity, and One Dimensional Scalar Constancy as features for image recognition and classifying benthic habitats in an image with the coastal areas of Hinatuan, Surigao Del Sur, Philippines as the study area. The study area is composed of four datasets, namely: (a) Blk66L005, (b) Blk66L021, (c) Blk66L024, and (d) Blk66L0114. SVM optimization was performed in Matlab® software with the help of Parallel Computing Toolbox to hasten the SVM computing speed. The image used for collecting samples for SVM procedure was Blk66L0114 in which a total of 134,516 sample objects of mangrove, possible coral existence with rocks, sand, sea, fish pens and sea grasses were collected and processed. The collected samples were then used as training sets for the supervised learning algorithm and for the creation of class definitions. The learned hyper-planes separating one class from another in the multi-dimensional feature space can be thought of as a super feature which will then be used in developing the C (classifier) rule set in eCognition® software. The classification results of the sampling site yielded an accuracy of 98.85% which confirms the reliability of remote sensing techniques and analysis employed to orthophotos like the CIELAB, Color Intensity and One dimensional scalar constancy and the use of SVM classification algorithm in classifying benthic habitats.

  13. THE APPLICATION OF SUPPORT VECTOR MACHINE (SVM USING CIELAB COLOR MODEL, COLOR INTENSITY AND COLOR CONSTANCY AS FEATURES FOR ORTHO IMAGE CLASSIFICATION OF BENTHIC HABITATS IN HINATUAN, SURIGAO DEL SUR, PHILIPPINES

    Directory of Open Access Journals (Sweden)

    J. E. Cubillas

    2016-06-01

    Full Text Available This study demonstrates the application of CIELAB, Color intensity, and One Dimensional Scalar Constancy as features for image recognition and classifying benthic habitats in an image with the coastal areas of Hinatuan, Surigao Del Sur, Philippines as the study area. The study area is composed of four datasets, namely: (a Blk66L005, (b Blk66L021, (c Blk66L024, and (d Blk66L0114. SVM optimization was performed in Matlab® software with the help of Parallel Computing Toolbox to hasten the SVM computing speed. The image used for collecting samples for SVM procedure was Blk66L0114 in which a total of 134,516 sample objects of mangrove, possible coral existence with rocks, sand, sea, fish pens and sea grasses were collected and processed. The collected samples were then used as training sets for the supervised learning algorithm and for the creation of class definitions. The learned hyper-planes separating one class from another in the multi-dimensional feature space can be thought of as a super feature which will then be used in developing the C (classifier rule set in eCognition® software. The classification results of the sampling site yielded an accuracy of 98.85% which confirms the reliability of remote sensing techniques and analysis employed to orthophotos like the CIELAB, Color Intensity and One dimensional scalar constancy and the use of SVM classification algorithm in classifying benthic habitats.

  14. Seeing sounds and hearing colors: an event-related potential study of auditory-visual synesthesia.

    Science.gov (United States)

    Goller, Aviva I; Otten, Leun J; Ward, Jamie

    2009-10-01

    In auditory-visual synesthesia, sounds automatically elicit conscious and reliable visual experiences. It is presently unknown whether this reflects early or late processes in the brain. It is also unknown whether adult audiovisual synesthesia resembles auditory-induced visual illusions that can sometimes occur in the general population or whether it resembles the electrophysiological deflection over occipital sites that has been noted in infancy and has been likened to synesthesia. Electrical brain activity was recorded from adult synesthetes and control participants who were played brief tones and required to monitor for an infrequent auditory target. The synesthetes were instructed to attend either to the auditory or to the visual (i.e., synesthetic) dimension of the tone, whereas the controls attended to the auditory dimension alone. There were clear differences between synesthetes and controls that emerged early (100 msec after tone onset). These differences tended to lie in deflections of the auditory-evoked potential (e.g., the auditory N1, P2, and N2) rather than the presence of an additional posterior deflection. The differences occurred irrespective of what the synesthetes attended to (although attention had a late effect). The results suggest that differences between synesthetes and others occur early in time, and that synesthesia is qualitatively different from similar effects found in infants and certain auditory-induced visual illusions in adults. In addition, we report two novel cases of synesthesia in which colors elicit sounds, and vice versa. PMID:18823243

  15. Four issues concerning colour constancy and relational colour constancy

    NARCIS (Netherlands)

    Foster, DH; Nascimento, SMC; Craven, BJ; Linnell, KJ; Cornelissen, FW; Brenner, E

    1997-01-01

    Four issues concerning colour constance and relational colour constancy are briefly considered: (I) the equivalence of colour constancy and relational colour constancy; (2) the dependence of relational colour constancy on ratios of cone excitations due to light from different reflecting surfaces, an

  16. Immediate colour constancy

    OpenAIRE

    Foster DH, Craven BJ, Sale ERH

    1992-01-01

    Colour constancy is traditionally interpreted as the stable appearance of the colour of a surface despite changes in the spectral composition of the illumination. When colour constancy has been assessed quantitatively, however, by observers making matches between surfaces illuminated by different sources, its completeness has been found to be poor. An alternative operational approach to colour constancy may be taken which concentrates instead on detecting the underlying chromatic relationship...

  17. Rethinking Colour Constancy.

    Directory of Open Access Journals (Sweden)

    Alexander D Logvinenko

    Full Text Available Colour constancy needs to be reconsidered in light of the limits imposed by metamer mismatching. Metamer mismatching refers to the fact that two objects reflecting metameric light under one illumination may reflect non-metameric light under a second; so two objects appearing as having the same colour under one illuminant can appear as having different colours under a second. Yet since Helmholtz, object colour has generally been believed to remain relatively constant. The deviations from colour constancy registered in experiments are usually thought to be small enough that they do not contradict the notion of colour constancy. However, it is important to determine how the deviations from colour constancy relate to the limits metamer mismatching imposes on constancy. Hence, we calculated metamer mismatching's effect for the 20 Munsell papers and 8 pairs of illuminants employed in the colour constancy study by Logvinenko and Tokunaga and found it to be so extensive that the two notions-metamer mismatching and colour constancy-must be mutually exclusive. In particular, the notion of colour constancy leads to some paradoxical phenomena such as the possibility of 20 objects having the same colour under chromatic light dispersing into a hue circle of colours under neutral light. Thus, colour constancy refers to a phenomenon, which because of metamer mismatching, simply cannot exist. Moreover, it obscures the really important visual phenomenon; namely, the alteration of object colours induced by illumination change. We show that colour is not an independent, intrinsic attribute of an object, but rather an attribute of an object/light pair, and then define a concept of material colour in terms of equivalence classes of such object/light pairs. We suggest that studying the shift in material colour under a change in illuminant will be more fruitful than pursuing colour constancy's false premise that colour is an intrinsic attribute of an object.

  18. Rethinking Colour Constancy.

    Science.gov (United States)

    Logvinenko, Alexander D; Funt, Brian; Mirzaei, Hamidreza; Tokunaga, Rumi

    2015-01-01

    Colour constancy needs to be reconsidered in light of the limits imposed by metamer mismatching. Metamer mismatching refers to the fact that two objects reflecting metameric light under one illumination may reflect non-metameric light under a second; so two objects appearing as having the same colour under one illuminant can appear as having different colours under a second. Yet since Helmholtz, object colour has generally been believed to remain relatively constant. The deviations from colour constancy registered in experiments are usually thought to be small enough that they do not contradict the notion of colour constancy. However, it is important to determine how the deviations from colour constancy relate to the limits metamer mismatching imposes on constancy. Hence, we calculated metamer mismatching's effect for the 20 Munsell papers and 8 pairs of illuminants employed in the colour constancy study by Logvinenko and Tokunaga and found it to be so extensive that the two notions-metamer mismatching and colour constancy-must be mutually exclusive. In particular, the notion of colour constancy leads to some paradoxical phenomena such as the possibility of 20 objects having the same colour under chromatic light dispersing into a hue circle of colours under neutral light. Thus, colour constancy refers to a phenomenon, which because of metamer mismatching, simply cannot exist. Moreover, it obscures the really important visual phenomenon; namely, the alteration of object colours induced by illumination change. We show that colour is not an independent, intrinsic attribute of an object, but rather an attribute of an object/light pair, and then define a concept of material colour in terms of equivalence classes of such object/light pairs. We suggest that studying the shift in material colour under a change in illuminant will be more fruitful than pursuing colour constancy's false premise that colour is an intrinsic attribute of an object. PMID:26356217

  19. 基于颜色恒常性的低照度图像视见度增强%Color Constancy-based Visibility Enhancement of Color Images in Low-light Conditions

    Institute of Scientific and Technical Information of China (English)

    禹晶; 李大鹏; 廖庆敏

    2011-01-01

    在彩色成像过程中,低照度是导致图像降质的一个重要因素.本文提出了一种新的基于颜色恒常性的低照度图像视见度增强算法.为了避免场景光源的影响,提出了像素有效集的概念.基于灰色调算法的灰度像素假设,利用有效像素估计光照的颜色;在后处理阶段,利用有效像素的灰度级范围确定直方图剪裁的上下限.实验表明,算法有效地校正了图像的颜色、对比度和亮度,从而增强了图像的视见度,且不会产生Retinex算法所固有的灰化效应和Halo效应.%Color imaging in low-light conditions is often significantly degraded by insufficient lighting and color cast. In this paper, we present a novel color constancy-based method to enhance the visibility of low-light images. Due to the occurrence of the scene illuminant or specular highlights, inhomogeneous illumination affects the estimation of the illuminant color across the scene. Thus in the image, an active set of pixel values is defined to reduce their effects. We then propose an improvement on the gray-pixel assumption imposed by the shades-of-gray algorithm using the active set. The improved shades-of-gray algorithm is applied to low-light image visibility enhancement for cast removal. Limits of histogram clipping are found in the active set in the post-processing step that is added to render the resulting image with a good lightness and contrast range. Results on a variety of low-light images demonstrate that the proposed method can achieve a good correction for lightness, contrast and color fidelity without local graying-out artifacts or halo artifacts intrinsic to Retinex approaches.

  20. Colour constancy in insects.

    Science.gov (United States)

    Chittka, Lars; Faruq, Samia; Skorupski, Peter; Werner, Annette

    2014-06-01

    Colour constancy is the perceptual phenomenon that the colour of an object appears largely unchanged, even if the spectral composition of the illuminating light changes. Colour constancy has been found in all insect species so far tested. Especially the pollinating insects offer a remarkable opportunity to study the ecological significance of colour constancy since they spend much of their adult lives identifying and choosing between colour targets (flowers) under continuously changing ambient lighting conditions. In bees, whose colour vision is best studied among the insects, the compensation provided by colour constancy is only partial and its efficiency depends on the area of colour space. There is no evidence for complete 'discounting' of the illuminant in bees, and the spectral composition of the light can itself be used as adaptive information. In patchy illumination, bees adjust their spatial foraging to minimise transitions between variously illuminated zones. Modelling allows the quantification of the adaptive benefits of various colour constancy mechanisms in the economy of nature. We also discuss the neural mechanisms and cognitive operations that might underpin colour constancy in insects. PMID:24647930

  1. Rethinking Colour Constancy

    OpenAIRE

    Logvinenko, Alexander D.; Brian Funt; Hamidreza Mirzaei; Rumi Tokunaga

    2015-01-01

    Colour constancy needs to be reconsidered in light of the limits imposed by metamer mismatching. Metamer mismatching refers to the fact that two objects reflecting metameric light under one illumination may reflect non-metameric light under a second; so two objects appearing as having the same colour under one illuminant can appear as having different colours under a second. Yet since Helmholtz, object colour has generally been believed to remain relatively constant. The deviations from colou...

  2. Lightness constancy: Object identity and temporal integration

    Directory of Open Access Journals (Sweden)

    Zdravković Sunčica

    2008-01-01

    Full Text Available Studies of lightness constancy typically involve the comparison of two objects of the same shade that have been placed under different illuminations. In this study, we introduce factors such as object identity and immediate prior experience to measure the effect of these manipulations on constancy. In the first experiment, conditions sufficient to reproduce classical constancy failure (illumination difference, target values, articulation level were determined. In the second experiment a lightness judgment was made for a gray target that was then seen to move into another illumination level for the second match. Motion was used in an attempt to stress the target’s identity. The shade was still judged significantly lighter when placed under the higher than under the lower illumination. Failure of constancy thus occurred even when object identity was not in question. In the third experiment a priming paradigm was used, to assess the strength of constancy: one shade would appear in one illumination level and another shade in the other illumination level. Motion was used to trick observers into thinking that only a single object was presented. The estimated shade varied as a function of the shade of the prime. In the last experiment, observers were asked to make another match when the object was removed from view: the match of its true color independent of illumination. The value of this match-from-memory was based on the value obtained in the higher illumination level. Taken together, the experiments show that through object identity, immediate prior experience can influence lightness in systematic fashion.

  3. Synaesthesia and colour constancy.

    Science.gov (United States)

    Erskine, Holly; Mattingley, Jason B; Arnold, Derek H

    2013-04-01

    Grapheme-colour synaesthesia is an atypical condition characterized by the perception of colours when reading achromatic text. We investigated the level of colour processing responsible for these experiences. To do so, we tapped a central characteristic of colour perception. In different lighting conditions the same wavelength of light can prompt the perception of different colours. This helps humans recognize distinctive coloured objects despite changes in illumination. We wanted to see if synaesthetic colours were generated at a neural locus that was susceptible to colour constancy analyses. We used colour matching and naming tasks to examine interactions between simulated coloured illuminants and synaesthetic colours. Neither synaesthetic colour matching or naming was impacted. This contrasted with non-synaesthetic control participants, who performed the colour-matching task with graphemes physically coloured to mimic synaesthesia. Our data suggest that synaesthetic colour signals are not generated at lower-levels of colour processing, but are introduced at higher levels of analysis and are therefore not impacted by the processes responsible for perceptual constancy. PMID:22487049

  4. The Book of Touch edited by Constance Classen

    OpenAIRE

    Redhead, Professor Steve

    2006-01-01

    Acclaimed author Constance Classen’s edited collection of sensual studies, The Book of Touch, is an intriguing contribution to the already excellent Sensory Formations series published by Berg. Other books in the series which I have seen include The Auditory Culture Reader (superb for anyone teaching the regulation, production and consumption of popular music culture) and The Visual Culture Reader (perfect for film and television studies). Other titles which I have yet to investigate from the...

  5. Color contrast processing in human striate cortex

    OpenAIRE

    Kentridge, R. W.; Heywood, C. A.; Weiskrantz, L.

    2007-01-01

    Color constancy refers to the unchanging nature of the perceived color of an object despite considerable variation in the wavelength composition of the light illuminating it. The color contrasts between objects and their backgrounds play a crucial role in color constancy. We tested a patient whose right striate cortex had been removed and demonstrated that he made no use of color contrast in judging color appearance but instead made judgments based simply on wavelength comparison. This was sh...

  6. Sensory Underdetermination and Perceptual Constancy

    OpenAIRE

    Crockett, Damon

    2015-01-01

    This project has as its focus a pair of related phenomena central to human perception. The first is the underdetermination of perceptual content by sensor input, and the second is a class of mechanisms designed to transform impoverished sensor input into useful perceptual content, mechanisms commonly called `perceptual constancies'. The goal of this project is to discuss a particularly difficult form of sensory underdetermination I call \\textit{stacking}, a \\textit{co-local} sensory conflatio...

  7. An operational approach to colour constancy

    OpenAIRE

    Craven, BJ; Foster, DH

    1992-01-01

    Colour constancy is traditionally defined as the invariance of perceived surface colours under changes in the spectral composition of the illuminant. Existing quantitative studies show that, by this definition, human subjects show poor colour constancy. A different and complementary aspect of colour constancy is considered which is concerned with the ability of a subject to attribute correctly changes in the colour appearance of a scene either to changes in reflecting properties of the surfac...

  8. Lightness constancy: ratio invariance and luminance profile

    OpenAIRE

    Soranzo, Alessandro; Galmonde, Alessandro; Agostini, Tiziano

    2009-01-01

    The term simultaneous lightness constancy describes the capacity of the visual system to perceive equal reflecting surfaces as having the same lightness despite lying in different illumination fields. In some cases, however, a lightness constancy failure occurs; that is, equal reflecting surfaces appear different in lightness when differently illuminated. An open question is whether the luminance profile of the illumination edges affects simultaneous lightness constancy even when the ra...

  9. The CONSTANCES cohort: an open epidemiological laboratory

    Directory of Open Access Journals (Sweden)

    Zins Marie

    2010-08-01

    Full Text Available Abstract Background Prospective cohorts represent an essential design for epidemiological studies and allow for the study of the combined effects of lifestyle, environment, genetic predisposition, and other risk factors on a large variety of disease endpoints. The CONSTANCES cohort is intended to provide public health information and to serve as an "open epidemiologic laboratory" accessible to the epidemiologic research community. Although designed as a "general-purpose" cohort with very broad coverage, it will particularly focus on occupational and social determinants of health, and on aging. Methods/Design The CONSTANCES cohort is designed as a randomly selected representative sample of French adults aged 18-69 years at inception; 200,000 subjects will be included over a five-year period. At inclusion, the selected subjects will be invited to fill a questionnaire and to attend a Health Screening Center (HSC for a comprehensive health examination: weight, height, blood pressure, electrocardiogram, vision, auditory, spirometry, and biological parameters; for those aged 45 years and older, a specific work-up of functional, physical, and cognitive capacities will be performed. A biobank will be set up. The follow-up includes a yearly self-administered questionnaire, and a periodic visit to an HSC. Social and work-related events and health data will be collected from the French national retirement, health and death databases. The data that will be collected include social and demographic characteristics, socioeconomic status, life events, behaviors, and occupational factors. The health data will cover a wide spectrum: self-reported health scales, reported prevalent and incident diseases, long-term chronic diseases and hospitalizations, sick-leaves, handicaps, limitations, disabilities and injuries, healthcare utilization and services provided, and causes of death. To take into account non-participation at inclusion and attrition throughout the

  10. Computational color technology

    CERN Document Server

    Kang, Henry R

    2006-01-01

    Henry Kang provides the fundamental color principles and mathematical tools to prepare the reader for a new era of color reproduction, and for subsequent applications in multispectral imaging, medical imaging, remote sensing, and machine vision. This book is intended to bridge the gap between color science and computational color technology, putting color adaptation, color constancy, color transforms, color display, and color rendition in the domain of vector-matrix representations and theories. Computational Color Technology deals with color digital images on the spectral level using vector-m

  11. Working Memory Is Related to Perceptual Processing: A Case from Color Perception

    Science.gov (United States)

    Allen, Elizabeth C.; Beilock, Sian L.; Shevell, Steven K.

    2011-01-01

    We explored the relation between individual differences in working memory (WM) and color constancy, the phenomenon of color perception that allows us to perceive the color of an object as relatively stable under changes in illumination. Successive color constancy (measured by first viewing a colored surface under a particular illumination and…

  12. Analysis of the retinex theory of color vision

    Science.gov (United States)

    Brainard, D. H.; Wandell, B. A.

    1986-01-01

    Land's (1983) retinex algorithm is a model of human color constancy. The retinex algorithm is analyzed and its general properties are discussed. It is shown that the algorithm is too sensitive to changes in the color of nearby objects to serve as an adequate model of human color constancy.

  13. Lightness constancy and illumination discounting.

    Science.gov (United States)

    Logvinenko, Alexander D; Tokunaga, Rumi

    2011-08-01

    Contrary to the implication of the term "lightness constancy", asymmetric lightness matching has never been found to be perfect unless the scene is highly articulated (i.e., contains a number of different reflectances). Also, lightness constancy has been found to vary for different observers, and an effect of instruction (lightness vs. brightness) has been reported. The elusiveness of lightness constancy presents a great challenge to visual science; we revisit these issues in the following experiment, which involved 44 observers in total. The stimuli consisted of a large sheet of black paper with a rectangular spotlight projected onto the lower half and 40 squares of various shades of grey printed on the upper half. The luminance ratio at the edge of the spotlight was 25, while that of the squares varied from 2 to 16. Three different instructions were given to observers: They were asked to find a square in the upper half that (i) looked as if it was made of the same paper as that on which the spotlight fell (lightness match), (ii) had the same luminance contrast as the spotlight edge (contrast match), or (iii) had the same brightness as the spotlight (brightness match). Observers made 10 matches of each of the three types. Great interindividual variability was found for all three types of matches. In particular, the individual Brunswik ratios were found to vary over a broad range (from .47 to .85). That is, lightness matches were found to be far from veridical. Contrast matches were also found to be inaccurate, being on average, underestimated by a factor of 3.4. Articulation was found to essentially affect not only lightness, but contrast and brightness matches as well. No difference was found between the lightness and luminance contrast matches. While the brightness matches significantly differed from the other matches, the difference was small. Furthermore, the brightness matches were found to be subject to the same interindividual variability and the same

  14. Kuu plaat : Galaktlan "Constance". Plaadid kauplusest Lasering

    Index Scriptorium Estoniae

    2005-01-01

    Heliplaatidest: Galaktlan "Constance", Bonnie "Prince" Billy & Matt Sweeney "Superwolf", Hinkus feat. Maarja "Look around", Noizmakaz "Valitud mõtted", Hedvig Hanson & Andre Maaker "You Bring Me Yoy", Nancy Sinatra "Nancy Sinatra"

  15. How temporal cues can aid colour constancy

    OpenAIRE

    Foster, David H.; Amano, Kinjiro; Nascimento, Sérgio M. C.

    2000-01-01

    Colour constancy assessed by asymmetric simultaneous colour matching usually reveals limited levels of performance in the unadapted eye. Yet observers can readily discriminate illuminant changes on a scene from changes in the spectral reflectances of the surfaces making up the scene. This ability is probably based on judgements of relational colour constancy, in turn based on the physical stability of spatial ratios of cone excitations under illuminant changes. Evidence is presented suggestin...

  16. Colour constancy: human mechanisms and machine algorithms

    OpenAIRE

    Williams, C B

    1995-01-01

    This thesis describes a quantitative experimental investigation into instantaneous colour constancy in humans. Colour constancy may be defined as the ability of the visual system to maintain a constant colour percept of a surface despite varying conditions of illumination. Instantaneous, in this context, refers to effects which happen very rapidly with the change of illumination, rather than those which may be due to long term adaptation of the photoreceptors. The results of experiments are d...

  17. Colour Constancy Techniques for Re-Recognition of Pedestrians from Multiple Surveillance Cameras

    OpenAIRE

    Colombo, Alberto; Orwell, James; Velastin, Sergio

    2008-01-01

    International audience This paper presents work towards a system for tracking the movements of a pedestrian as they move between the multiple sensors comprising a surveillance system. The colour appearance of the observations is an important cue: it is useful to achieve good color constancy between the color values associated with each camera. A novel method for estimating the appropriate transform between each camera's colour space is proposed, using covariance of the foreground data coll...

  18. Temporal-envelope constancy of speech in rooms and the perceptual weighting of frequency bands.

    Science.gov (United States)

    Watkins, Anthony J; Raimond, Andrew P; Makin, Simon J

    2011-11-01

    Three experiments measured constancy in speech perception, using natural-speech messages or noise-band vocoder versions of them. The eight vocoder-bands had equally log-spaced center-frequencies and the shapes of corresponding "auditory" filters. Consequently, the bands had the temporal envelopes that arise in these auditory filters when the speech is played. The "sir" or "stir" test-words were distinguished by degrees of amplitude modulation, and played in the context; "next you'll get _ to click on." Listeners identified test-words appropriately, even in the vocoder conditions where the speech had a "noise-like" quality. Constancy was assessed by comparing the identification of test-words with low or high levels of room reflections across conditions where the context had either a low or a high level of reflections. Constancy was obtained with both the natural and the vocoded speech, indicating that the effect arises through temporal-envelope processing. Two further experiments assessed perceptual weighting of the different bands, both in the test word and in the context. The resulting weighting functions both increase monotonically with frequency, following the spectral characteristics of the test-word's [s]. It is suggested that these two weighting functions are similar because they both come about through the perceptual grouping of the test-word's bands. PMID:22087906

  19. Spatial constancy mechanisms in motor control.

    Science.gov (United States)

    Medendorp, W Pieter

    2011-02-27

    The success of the human species in interacting with the environment depends on the ability to maintain spatial stability despite the continuous changes in sensory and motor inputs owing to movements of eyes, head and body. In this paper, I will review recent advances in the understanding of how the brain deals with the dynamic flow of sensory and motor information in order to maintain spatial constancy of movement goals. The first part summarizes studies in the saccadic system, showing that spatial constancy is governed by a dynamic feed-forward process, by gaze-centred remapping of target representations in anticipation of and across eye movements. The subsequent sections relate to other oculomotor behaviour, such as eye-head gaze shifts, smooth pursuit and vergence eye movements, and their implications for feed-forward mechanisms for spatial constancy. Work that studied the geometric complexities in spatial constancy and saccadic guidance across head and body movements, distinguishing between self-generated and passively induced motion, indicates that both feed-forward and sensory feedback processing play a role in spatial updating of movement goals. The paper ends with a discussion of the behavioural mechanisms of spatial constancy for arm motor control and their physiological implications for the brain. Taken together, the emerging picture is that the brain computes an evolving representation of three-dimensional action space, whose internal metric is updated in a nonlinear way, by optimally integrating noisy and ambiguous afferent and efferent signals. PMID:21242137

  20. Colour constancy under simultaneous changes in surface position and illuminant.

    OpenAIRE

    Amano, Kinjiro; Foster, David H.

    2004-01-01

    Two kinds of constancy underlie the everyday perception of surface colour: constancy under changes in illuminant and constancy under changes in surface position. Classically, these two constancies seem to place conflicting demands on the visual system: to both take into account the region surrounding a surface and also discount it. It is shown here, however, that the ability of observers to make surface-colour matches across simultaneous changes in test-surface position and illuminant in comp...

  1. On the constancy of light speed

    OpenAIRE

    Rouf, Abdul

    2009-01-01

    Method given for intuitively visualizing constancy of light speed. Using mass-energy equivalence, we can show with the help of simple thought experiments, that velocity time dilation and gravitational time dilation are a necessary consequence of principle of relativity. Speed of light is discussed in the context of each kind of time dilation.

  2. Auditory Display

    DEFF Research Database (Denmark)

    volume. The conference's topics include auditory exploration of data via sonification and audification; real time monitoring of multivariate date; sound in immersive interfaces and teleoperation; perceptual issues in auditory display; sound in generalized computer interfaces; technologies supporting...... auditory display creation; data handling for auditory display systems; applications of auditory display....

  3. Chromatic aberration and the roles of double-opponent and color-luminance neurons in color vision

    NARCIS (Netherlands)

    Vladusich, Tony

    2007-01-01

    How does the visual cortex encode color? I summarize a theory in which cortical double-opponent color neurons perform a role in color constancy and a complementary set of color-luminance neurons function to selectively correct for color fringes induced by chromatic aberration in the eye. The theory

  4. The development of cognitive gender constancy and sex role preferences.

    Science.gov (United States)

    Marcus, D E; Overton, W F

    1978-06-01

    The chief purpose of this study was to examine the development of stable concepts of "boy" and "girl" (gender identity constancy) in kindergartners and first and second graders. Gender constancy was explored in relation to cognitive level (assessed both by grade and conservation measures); whether the concept was applied to the subject himself or to another child; whether the concept was applied to live children or pictorial representations; and sex role preferences (games, television characters, peer preferences). In support of a cognitive-developmental position, gender constancy was found to be related to cognitive level, and most children conformed to a developmental sequence (Guttman scalogram) in which conservation preceded gender constancy. Gender constancy performance was better when the concept was applied to the self versus another child and when applied to pictorial representations versus live forms. Gender constancy was not related to sex role preferences.

  5. Auditory Processing Disorders

    Science.gov (United States)

    Auditory Processing Disorders Auditory processing disorders (APDs) are referred to by many names: central auditory processing disorders , auditory perceptual disorders , and central auditory disorders . APDs ...

  6. Novel colour constancy algorithms for digital colour imagery

    OpenAIRE

    Shi, Lilong

    2009-01-01

    Colour constancy algorithms differ in their derivation, implementation, performance and assumptions. The focus of the research presented in this thesis is to discover colour constancy solutions to recover surface colours, or equivalently, to estimate the illumination, of single light source in a given scene. Several colour constancy models will be proposed. These methods have different methodologies and constraints. For example, a method can be constrained on a particular model surface materi...

  7. PERCEPTUAL CONSTANCY AND CONTEXTUAL ENHANCEMENT CONSTANCIA PERCEPTUAL Y MEJORAMIENTO CONTEXTUAL

    Directory of Open Access Journals (Sweden)

    HERIBERTO AVELINO

    2010-01-01

    Full Text Available The perception of the acoustic world surrounding us very often is different from its physical properties. Our mental representation of the sounds that we are exposed to are not in a one to one correspondence with the sounds we sense. Auditory objects and their environments are categorized and loaded in memory so that recognition of complex dynamic scenes are perceived optimally. Precise identification of voices and linguistic objects are crucial for effective communication. However, the normal context of hearing contains multiple, competing and noisy sources. In such disadvantageous conditions the identity of the percepts is more efficient if they are stored in memory. The results of the present study offer experimental evidence that high-level cognitive processes might constrain basic auditory mechanisms involved in identifying phonemic tone to guarantee perceptual constancy. The results showing a better identification of tones in contexts that are inveresely proportional to their frequency support the idea that peripheral auditory processing enhances the identification of the tones by a general function of contextual contrast.La percepción del mundo acústico que nos rodea es a menudo diferente de sus propiedades físicas. Nuestra representación mental de los sonidos a los que estamos expuestos no están en una correspondencia unívoca con los sonidos que sentimos. Los objetos auditivos y sus contextos son categorizados y acumulados en la memoria de forma tal que el reconocimiento de escenas dinámicas complejas son percibidas óptimamente. La identificación precisa de voces y objetos lingüísticos son cruciales para la comunicación efectiva. Sin embargo, el contexto normal de la escucha contiene fuentes múltiples, con ruido y en competencia. En estas condiciones de desventaja la identidad de los perceptos es más eficiente si son almacenados en la memoria. Los resultados del presente estudio ofrecen evidencia experimental de que

  8. Scene Context Dependency of Pattern Constancy of Time Series Imagery

    Science.gov (United States)

    Woodell, Glenn A.; Jobson, Daniel J.; Rahman, Zia-ur

    2008-01-01

    A fundamental element of future generic pattern recognition technology is the ability to extract similar patterns for the same scene despite wide ranging extraneous variables, including lighting, turbidity, sensor exposure variations, and signal noise. In the process of demonstrating pattern constancy of this kind for retinex/visual servo (RVS) image enhancement processing, we found that the pattern constancy performance depended somewhat on scene content. Most notably, the scene topography and, in particular, the scale and extent of the topography in an image, affects the pattern constancy the most. This paper will explore these effects in more depth and present experimental data from several time series tests. These results further quantify the impact of topography on pattern constancy. Despite this residual inconstancy, the results of overall pattern constancy testing support the idea that RVS image processing can be a universal front-end for generic visual pattern recognition. While the effects on pattern constancy were significant, the RVS processing still does achieve a high degree of pattern constancy over a wide spectrum of scene content diversity, and wide ranging extraneousness variations in lighting, turbidity, and sensor exposure.

  9. Chromatic aberration and the roles of double-opponent and color-luminance neurons in color vision.

    Science.gov (United States)

    Vladusich, Tony

    2007-03-01

    How does the visual cortex encode color? I summarize a theory in which cortical double-opponent color neurons perform a role in color constancy and a complementary set of color-luminance neurons function to selectively correct for color fringes induced by chromatic aberration in the eye. The theory may help to resolve an ongoing debate concerning the functional properties of cortical receptive fields involved in color coding.

  10. Sensory, computational and cognitive components of human colour constancy

    OpenAIRE

    Smithson, H. E.

    2005-01-01

    When the illumination on a scene changes, so do the visual signals elicited by that scene. In spite of these changes, the objects within a scene tend to remain constant in their apparent colour. We start this review by discussing the psychophysical procedures that have been used to quantify colour constancy. The transformation imposed on the visual signals by a change in illumination dictates what the visual system must ‘undo’ to achieve constancy. The problem is mathematically underdetermine...

  11. Constancy and inconstancy in categorical colour perception

    OpenAIRE

    Roca Vilà, Jordi

    2013-01-01

    Als preliminars: The research described in this book was carried out at the Computer Vision Center El reconeixement d'objectes és potser la tasca més important que un sistema autònom, ja sigui biològic o artificial, necessita realitzar. En el context de la visió humana, això s'aconsegueix parcialment a través del reconeixement del color de les superfícies malgrat els canvis en la distribució espectral de la llum, propietat anomenada constància de color. El reconeixement correcte del color ...

  12. Digital color acquisition, perception, coding and rendering

    CERN Document Server

    Fernandez-Maloigne, Christine; Macaire, Ludovic

    2013-01-01

    In this book the authors identify the basic concepts and recent advances in the acquisition, perception, coding and rendering of color. The fundamental aspects related to the science of colorimetry in relation to physiology (the human visual system) are addressed, as are constancy and color appearance. It also addresses the more technical aspects related to sensors and the color management screen. Particular attention is paid to the notion of color rendering in computer graphics. Beyond color, the authors also look at coding, compression, protection and quality of color images and videos.

  13. Auditory Neuropathy

    Science.gov (United States)

    ... field differ in their opinions about the potential benefits of hearing aids, cochlear implants, and other technologies for people with auditory neuropathy. Some professionals report that hearing aids and personal listening devices such as frequency modulation (FM) systems are ...

  14. Some tests for parameter constancy in cointegrated VAR-models

    DEFF Research Database (Denmark)

    Hansen, Henrik; Johansen, Søren

    1999-01-01

    Some methods for the evaluation of parameter constancy in vector autoregressive (VAR) models are discussed. Two different ways of re-estimating the VAR model are proposed; one in which all parameters are estimated recursively based upon the likelihood function for the first observations, and anot...... be applied to test the constancy of the long-run parameters in the cointegrated VAR-model. All results are illustrated using a model for the term structure of interest rates on US Treasury securities. ....... Specifically we look at the time path of the eigenvalues using a new result on the asymptotic distribution of the estimated eigenvalues. Furthermore we show that the fluctuation test by Ploberger et al. (1989) and the Lagrange multiplier (LM) type test for constancy of parameters by Nyblom (1989) can...

  15. Local and relational judgements of surface colour : constancy indices and discrimination performance

    NARCIS (Netherlands)

    Van Es, Just J.; Vladusich, Tony; Cornelissen, Frans W.

    2007-01-01

    Colour constancy is generally assumed to arise from a combination of perceptual constancy mechanisms operating to partially discount illumination changes and relational mechanisms involved in judging the colour relationships between object surfaces. Here we examined the characteristics of these mech

  16. Seeing the song: left auditory structures may track auditory-visual dynamic alignment.

    Directory of Open Access Journals (Sweden)

    Julia A Mossbridge

    Full Text Available Auditory and visual signals generated by a single source tend to be temporally correlated, such as the synchronous sounds of footsteps and the limb movements of a walker. Continuous tracking and comparison of the dynamics of auditory-visual streams is thus useful for the perceptual binding of information arising from a common source. Although language-related mechanisms have been implicated in the tracking of speech-related auditory-visual signals (e.g., speech sounds and lip movements, it is not well known what sensory mechanisms generally track ongoing auditory-visual synchrony for non-speech signals in a complex auditory-visual environment. To begin to address this question, we used music and visual displays that varied in the dynamics of multiple features (e.g., auditory loudness and pitch; visual luminance, color, size, motion, and organization across multiple time scales. Auditory activity (monitored using auditory steady-state responses, ASSR was selectively reduced in the left hemisphere when the music and dynamic visual displays were temporally misaligned. Importantly, ASSR was not affected when attentional engagement with the music was reduced, or when visual displays presented dynamics clearly dissimilar to the music. These results appear to suggest that left-lateralized auditory mechanisms are sensitive to auditory-visual temporal alignment, but perhaps only when the dynamics of auditory and visual streams are similar. These mechanisms may contribute to correct auditory-visual binding in a busy sensory environment.

  17. Color image and video enhancement

    CERN Document Server

    Lecca, Michela; Smolka, Bogdan

    2015-01-01

    This text covers state-of-the-art color image and video enhancement techniques. The book examines the multivariate nature of color image/video data as it pertains to contrast enhancement, color correction (equalization, harmonization, normalization, balancing, constancy, etc.), noise removal and smoothing. This book also discusses color and contrast enhancement in vision sensors and applications of image and video enhancement.   ·         Focuses on enhancement of color images/video ·         Addresses algorithms for enhancing color images and video ·         Presents coverage on super resolution, restoration, in painting, and colorization.

  18. Gender Constancy and Same-Sex Imitation: A Developmental Study.

    Science.gov (United States)

    Perloff, Richard M.

    1982-01-01

    Fifty-one preschool children were interviewed individually to assess awareness of gender constancy and choice of same-sex models. Differences emerged between high and low gender-constant children when they were given a choice between imitating a same-sex model performing a relatively unpleasant task and imitating an opposite-sex model enacting a…

  19. Colour constancy for an unseen surface.

    OpenAIRE

    Norman, L.J.; Akins, K.; Heywood, C. A.; Kentridge, R. W.

    2014-01-01

    The illumination of a scene strongly affects our perception of objects in that scene, e.g., the pages of a book illuminated by candlelight will appear quite yellow relative to other types of artificial illuminants. Yet at the same time, the reader still judges the pages as white, their surface color unaffected by the interplay of paper and illuminant. It has been shown empirically [ 1 ] that we can indeed report two quite different interpretations of “color”: one is dependent on the constant ...

  20. Wind-induced baroclinic response of Lake Constance

    Directory of Open Access Journals (Sweden)

    Y. Wang

    Full Text Available We present results of various circulation scenarios for the wind-induced three-dimensional currents in Lake Constance, obtained with the aid of a semi-spectral semi-implicit finite difference code developed in Haidvogel et al. and Wang and Hutter. Internal Kelvin and Poincaré-type oscillations are demonstrated in the numerical results, whose periods depend upon the stratification and the geometry of the basin and agree well with measured data. By solving the eigenvalue problem of the linearized shallow water equations in the two-layered stratified Lake Constance, the interpretation of the oscillations as Kelvin and Poincaré-type waves is corroborated.

    Key words: Oceanography: general (limnology; numerical modeling – Oceanography: physical (internal and inertial waves

  1. Colour constancy of the swallowtail butterfly Papilio xuthus

    OpenAIRE

    Kinoshita, Michiyo; Arikawa, Kentaro; 充代, 木下

    2000-01-01

    We have recently shown that the Japanese yellow swallowtail butterfly Papilio xuthus uses colour vision when searching for food. In the field, these butterflies feed on nectar provided by flowers of various colours not only in direct sunlight but also in shaded places and on cloudy days, suggesting that they have colour constancy. Here, we tested this hypothesis. We trained newly emerged Papilio xuthus to feed on sucrose solution on a paper patch of a certain colour under white illumination. ...

  2. Shape from shading, colour constancy, and deutan colour vision deficiencies

    OpenAIRE

    Jakobsson, Torbjörn

    1996-01-01

    Four studies including ten experiments adresses interrelations between some major and classical issues in visual perception: 3-D perception, colour constancy, colour perception and colour vision deficiencies. The main experimental paradigm to investigate the issues is within that of simulated shape from shading. 3-D impressions are induced by projecting space-modulated illuminations onto flat surfaces (displays), varying the colours and layout of the displays and the colour and modulation of ...

  3. Target recognitions in multiple camera CCTV using colour constancy

    OpenAIRE

    Soori, U; Yuen, P.W.T.; I. Ibrahim; Han, J W; Hong, K.; Chen, W.T.; Merfort, C.; James, D; Richardson, M

    2013-01-01

    People tracking using colour feature in crowded scene through CCTV network have been a popular and at the same time a very difficult topic in computer vision. It is mainly because of the difficulty for the acquisition of intrinsic signatures of targets from a single view of the scene. Many factors, such as variable illumination conditions and viewing angles, will induce illusive modification of intrinsic signatures of targets. The objective of this paper is to verify if colour constancy (CC) ...

  4. Enhanced target detection in CCTV network system using colour constancy

    OpenAIRE

    Soori, Y

    2016-01-01

    The focus of this research is to study how targets can be more faithfully detected in a multi-camera CCTV network system using spectral feature for the detection. The objective of the work is to develop colour constancy (CC) methodology to help maintain the spectral feature of the scene into a constant stable state irrespective of variable illuminations and camera calibration issues. Unlike previous work in the field of target detection, two versions of CC algorithms have been developed d...

  5. Origin of fossil hydrocarbons in recent sediments of Lake Constance

    Energy Technology Data Exchange (ETDEWEB)

    Pickel, W.; Hagemann, H.W. (Technische Hochschule Aachen (Germany, F.R.). Lehrstuhl fuer Geologie, Geochemie und Lagerstaetten des Erdoels und der Kohle); Hollerbach, A. (Bundesanstalt fuer Geowissenschaften und Rohstoffe, Hannover (Germany, F.R.))

    An investigation was undertaken using a combination of petrographic and geochemical techniques to obtain information on the type, origin and amount of organic matter found in surface sediments of Lake Constance, as well as to check on possible sources of the hydrocarbons present. Forty samples, consisting of sedimentary and suspended material were taken from different lake areas. Since the products that could be identified are the same, it is rather difficult to differentiate between the natural input of hydrocarbons in Lake Constance by soil erosion and the input of technically applied hydrocarbons (lubricants, etc.). The organic geochemical results clearly show that parts of the hydrocarbons extractable from the Lake Constance sediments are derived from fossil organic material. This was confirmed by the detection of specific compounds. Type and distribution of the hydrocarbons, especially pentacyclic triterpanes and tricyclic terpanes indicate a dominant input of fossil organic matter from natural sources. Nevertheless no definite proof could be found that in the complex extract of the sediments the hydrocarbons indicating fossil organic matter are derived from natural sources and not from pollutants. (orig./EF).

  6. Effects of memory colour on colour constancy for unknown coloured objects

    OpenAIRE

    Granzier, Jeroen J. M.; Gegenfurtner, Karl R.

    2012-01-01

    The perception of an object's colour remains constant despite large variations in the chromaticity of the illumination—colour constancy. Hering suggested that memory colours, the typical colours of objects, could help in estimating the illuminant's colour and therefore be an important factor in establishing colour constancy. Here we test whether the presence of objects with diagnostical colours (fruits, vegetables, etc) within a scene influence colour constancy for unknown coloured objects in...

  7. Chromatic Illumination Discrimination Ability Reveals that Human Colour Constancy Is Optimised for Blue Daylight Illuminations

    OpenAIRE

    Bradley Pearce; Stuart Crichton; Michal Mackiewicz; Finlayson, Graham D.; Anya Hurlbert

    2014-01-01

    The phenomenon of colour constancy in human visual perception keeps surface colours constant, despite changes in their reflected light due to changing illumination. Although colour constancy has evolved under a constrained subset of illuminations, it is unknown whether its underlying mechanisms, thought to involve multiple components from retina to cortex, are optimised for particular environmental variations. Here we demonstrate a new method for investigating colour constancy using illuminat...

  8. Improving color correction across camera and illumination changes by contextual sample selection

    Science.gov (United States)

    Wannous, Hazem; Lucas, Yves; Treuillet, Sylvie; Mansouri, Alamin; Voisin, Yvon

    2012-04-01

    In many tasks of machine vision applications, it is important that recorded colors remain constant, in the real world scene, even under changes of the illuminants and the cameras. Contrary to the human vision system, a machine vision system exhibits inadequate adaptability to the variation of lighting conditions. Automatic white balance control available in commercial cameras is not sufficient to provide reproducible color classification. We address this problem of color constancy on a large image database acquired with varying digital cameras and lighting conditions. A device-independent color representation may be obtained by applying a chromatic adaptation transform, from a calibrated color checker pattern included in the field of view. Instead of using the standard Macbeth color checker, we suggest selecting judicious colors to design a customized pattern from contextual information. A comparative study demonstrates that this approach ensures a stronger constancy of the colors-of-interest before vision control thus enabling a wide variety of applications.

  9. An Experimental Test of the Effects of Gender Constancy on Sex Typing

    Science.gov (United States)

    Arthur, Andrea E.; Bigler, Rebecca S.; Ruble, Diane N.

    2009-01-01

    This study provides an experimental test of the hypothesis that level of gender constancy understanding affects children's sex typing. Preschool-age children (N = 62, mean age = 47 months) were randomly assigned to experimental lessons that taught that biological traits (including gender) are either fixed (pro-constancy condition) or mutable…

  10. Constancy and diversity in the flavivirus fusion peptide

    Science.gov (United States)

    Seligman, Stephen J

    2008-01-01

    Background Flaviviruses include the mosquito-borne dengue, Japanese encephalitis, yellow fever and West Nile and the tick-borne encephalitis viruses. They are responsible for considerable world-wide morbidity and mortality. Viral entry is mediated by a conserved fusion peptide containing 16 amino acids located in domain II of the envelope protein E. Highly orchestrated conformational changes initiated by exposure to acidic pH accompany the fusion process and are important factors limiting amino acid changes in the fusion peptide that still permit fusion with host cell membranes in both arthropod and vertebrate hosts. The cell-fusing related agents, growing only in mosquitoes or insect cell lines, possess a different homologous peptide. Results Analysis of 46 named flaviviruses deposited in the Entrez Nucleotides database extended the constancy in the canonical fusion peptide sequences of mosquito-borne, tick-borne and viruses with no known vector to include more recently-sequenced viruses. The mosquito-borne signature amino acid, G104, was also found in flaviviruses with no known vector and with the cell-fusion related viruses. Despite the constancy in the canonical sequences in pathogenic flaviviruses, mutations were surprisingly frequent with a 27% prevalence of nonsynonymous mutations in yellow fever virus fusion peptide sequences, and 0 to 7.4% prevalence in the others. Six of seven yellow fever patients whose virus had fusion peptide mutations died. In the cell-fusing related agents, not enough sequences have been deposited to estimate reliably the prevalence of fusion peptide mutations. However, the canonical sequences homologous to the fusion peptide and the pattern of disulfide linkages in protein E differed significantly from the other flaviviruses. Conclusion The constancy of the canonical fusion peptide sequences in the arthropod-borne flaviviruses contrasts with the high prevalence of mutations in most individual viruses. The discrepancy may be the

  11. Constancy and diversity in the flavivirus fusion peptide

    Directory of Open Access Journals (Sweden)

    Seligman Stephen J

    2008-02-01

    Full Text Available Abstract Background Flaviviruses include the mosquito-borne dengue, Japanese encephalitis, yellow fever and West Nile and the tick-borne encephalitis viruses. They are responsible for considerable world-wide morbidity and mortality. Viral entry is mediated by a conserved fusion peptide containing 16 amino acids located in domain II of the envelope protein E. Highly orchestrated conformational changes initiated by exposure to acidic pH accompany the fusion process and are important factors limiting amino acid changes in the fusion peptide that still permit fusion with host cell membranes in both arthropod and vertebrate hosts. The cell-fusing related agents, growing only in mosquitoes or insect cell lines, possess a different homologous peptide. Results Analysis of 46 named flaviviruses deposited in the Entrez Nucleotides database extended the constancy in the canonical fusion peptide sequences of mosquito-borne, tick-borne and viruses with no known vector to include more recently-sequenced viruses. The mosquito-borne signature amino acid, G104, was also found in flaviviruses with no known vector and with the cell-fusion related viruses. Despite the constancy in the canonical sequences in pathogenic flaviviruses, mutations were surprisingly frequent with a 27% prevalence of nonsynonymous mutations in yellow fever virus fusion peptide sequences, and 0 to 7.4% prevalence in the others. Six of seven yellow fever patients whose virus had fusion peptide mutations died. In the cell-fusing related agents, not enough sequences have been deposited to estimate reliably the prevalence of fusion peptide mutations. However, the canonical sequences homologous to the fusion peptide and the pattern of disulfide linkages in protein E differed significantly from the other flaviviruses. Conclusion The constancy of the canonical fusion peptide sequences in the arthropod-borne flaviviruses contrasts with the high prevalence of mutations in most individual viruses

  12. TARA and constance B mirror confinement experiments and theory

    International Nuclear Information System (INIS)

    The axisymmetric TARA central cell has been heated using aperture and double half turn ICRF antennas to produce stable plasma with β less than or equal to 0.2%. Parameters suitable for startup of thermal barriers with n = 3.5 x 1012/cm3 and Ti/sub perpendiculer/ approx. 30 eV have been reached. Hot electron plasmas with β less than or equal to 15% are obtained in the TARA and Constance quadrupoles. Electron cyclotron instabilities are analyzed. A new scheme for single frequency drift pumping with stochasticity by ICRF is proposed. ICRF modulated at the electron bounce frequency is shown to yield stochastic parallel electron heating for thermal barriers

  13. Quantitative studies of animal colour constancy: using the chicken as model.

    Science.gov (United States)

    Olsson, Peter; Wilby, David; Kelber, Almut

    2016-05-11

    Colour constancy is the capacity of visual systems to keep colour perception constant despite changes in the illumination spectrum. Colour constancy has been tested extensively in humans and has also been described in many animals. In humans, colour constancy is often studied quantitatively, but besides humans, this has only been done for the goldfish and the honeybee. In this study, we quantified colour constancy in the chicken by training the birds in a colour discrimination task and testing them in changed illumination spectra to find the largest illumination change in which they were able to remain colour-constant. We used the receptor noise limited model for animal colour vision to quantify the illumination changes, and found that colour constancy performance depended on the difference between the colours used in the discrimination task, the training procedure and the time the chickens were allowed to adapt to a new illumination before making a choice. We analysed literature data on goldfish and honeybee colour constancy with the same method and found that chickens can compensate for larger illumination changes than both. We suggest that future studies on colour constancy in non-human animals could use a similar approach to allow for comparison between species and populations. PMID:27170714

  14. Electron-cyclotron heating in the Constance 2 mirror experiment

    Energy Technology Data Exchange (ETDEWEB)

    Mauel, Michael E.

    1982-09-01

    Electron cyclotron heating of a highly-ionized plasma in mirror geometry is investigated. The experimental diagnosis of the electron energy distribution and the comparison of the results of this diagnosis with a two dimensional, time-dependent Fokker-Planck simulation are accomplished in four steps. (1) First, the power balance of the heated and unheated Constance 2 plasma is analyzed experimentally. It is concluded that the heated electrons escape the mirror at a rate dominated by a combination of the influx of cool electrons from outside the mirror and the increased loss rate of the ions. (2) The microwave parameters at the resonance zones are then calculated by cold-plasma ray tracing. High N/sub parallel/ waves are launched and for these waves, strong first-pass absorption is predicted. The absorption strength is qualitatively checked in the experiment by surrounding the plasma with non-reflecting liners. (3) A simplified quasilinear theory including the effect of N/sub parallel/ is developed to model the electrons. An analytic expression is derived for the RF-induced pump-out of the magnetically-confined warm electrons. Results of the Fokker-Planck simulations show the development of the electron energy distribution for several plasma conditions and verify the scaling of the analytic expression for RF-induced diffusion into the loss cone. (4) Sample x-ray and endloss data are presented, and the overall comparison between the simulation and experiment is discussed. The x-ray signals indicate that, for greater RF power, the hot electrondensity increases more rapidly than its temperature. The time history of the endloss data, illustrating RF-enhancement, suggests the predicted scaling for warm-electron pump-out. Finally, a comparison between the measured and predicted energy distribution shows that the bulk, warm and hot components of the heated Constance 2 electrons are indeed reproduced by the simulation.

  15. Electron-cyclotron heating in the Constance 2 mirror experiment

    International Nuclear Information System (INIS)

    Electron cyclotron heating of a highly-ionized plasma in mirror geometry is investigated. The experimental diagnosis of the electron energy distribution and the comparison of the results of this diagnosis with a two dimensional, time-dependent Fokker-Planck simulation are accomplished in four steps. (1) First, the power balance of the heated and unheated Constance 2 plasma is analyzed experimentally. It is concluded that the heated electrons escape the mirror at a rate dominated by a combination of the influx of cool electrons from outside the mirror and the increased loss rate of the ions. (2) The microwave parameters at the resonance zones are then calculated by cold-plasma ray tracing. High N/sub parallel/ waves are launched and for these waves, strong first-pass absorption is predicted. The absorption strength is qualitatively checked in the experiment by surrounding the plasma with non-reflecting liners. (3) A simplified quasilinear theory including the effect of N/sub parallel/ is developed to model the electrons. An analytic expression is derived for the RF-induced pump-out of the magnetically-confined warm electrons. Results of the Fokker-Planck simulations show the development of the electron energy distribution for several plasma conditions and verify the scaling of the analytic expression for RF-induced diffusion into the loss cone. (4) Sample x-ray and endloss data are presented, and the overall comparison between the simulation and experiment is discussed. The x-ray signals indicate that, for greater RF power, the hot electrondensity increases more rapidly than its temperature. The time history of the endloss data, illustrating RF-enhancement, suggests the predicted scaling for warm-electron pump-out. Finally, a comparison between the measured and predicted energy distribution shows that the bulk, warm and hot components of the heated Constance 2 electrons are indeed reproduced by the simulation

  16. Critical comments on ''on the constancy of the speed of light''

    International Nuclear Information System (INIS)

    Criticisms are answered on the new theory of the constancy of the speed of light. All criticisms are answered, and it is shown that the new theory is not logically inconsistent for the reasons expressed. 17 references

  17. Colour constancy from temporal cues: better matches with less variability under fast illuminant changes

    OpenAIRE

    Foster DH, Amano K, Nascimento SMC

    2001-01-01

    To test whether temporal transient cues could improve colour-constancy estimates, surface-colour matches were made across two Mondrian patterns illuminated by different daylights: the patterns were presented either in the same position in an alternating sequence or, as a control, simultaneously side-by-side. The degree of colour constancy was significantly higher with sequential stimulus presentation than with simultaneous presentation, in the best condition reaching 0.87 on a scale of 0 to 1...

  18. Comparison of flower constancy and foraging performance in three bumblebee species (Hymenoptera: Apidae: Bombus)

    OpenAIRE

    Raine, N.E.; Chittka, L.

    2005-01-01

    The three bumblebee species Bombus terrestris (Linnaeus 1758), Bombus lapidarius (Linnaeus 1758), and Bombus pascuorum (Scopoli 1763) showed consistent differences in their respective levels of flower constancy when foraging on three different pairs of flower species. B. terrestris was always the most flower constant, followed by B. lapidarius, with B. pascuorum the least flower constant species. These interspecific differences in flower constancy were related to foraging performance under fi...

  19. Chromatic illumination discrimination ability reveals that human colour constancy is optimised for blue daylight illuminations.

    Science.gov (United States)

    Pearce, Bradley; Crichton, Stuart; Mackiewicz, Michal; Finlayson, Graham D; Hurlbert, Anya

    2014-01-01

    The phenomenon of colour constancy in human visual perception keeps surface colours constant, despite changes in their reflected light due to changing illumination. Although colour constancy has evolved under a constrained subset of illuminations, it is unknown whether its underlying mechanisms, thought to involve multiple components from retina to cortex, are optimised for particular environmental variations. Here we demonstrate a new method for investigating colour constancy using illumination matching in real scenes which, unlike previous methods using surface matching and simulated scenes, allows testing of multiple, real illuminations. We use real scenes consisting of solid familiar or unfamiliar objects against uniform or variegated backgrounds and compare discrimination performance for typical illuminations from the daylight chromaticity locus (approximately blue-yellow) and atypical spectra from an orthogonal locus (approximately red-green, at correlated colour temperature 6700 K), all produced in real time by a 10-channel LED illuminator. We find that discrimination of illumination changes is poorer along the daylight locus than the atypical locus, and is poorest particularly for bluer illumination changes, demonstrating conversely that surface colour constancy is best for blue daylight illuminations. Illumination discrimination is also enhanced, and therefore colour constancy diminished, for uniform backgrounds, irrespective of the object type. These results are not explained by statistical properties of the scene signal changes at the retinal level. We conclude that high-level mechanisms of colour constancy are biased for the blue daylight illuminations and variegated backgrounds to which the human visual system has typically been exposed. PMID:24586299

  20. Chromatic illumination discrimination ability reveals that human colour constancy is optimised for blue daylight illuminations.

    Directory of Open Access Journals (Sweden)

    Bradley Pearce

    Full Text Available The phenomenon of colour constancy in human visual perception keeps surface colours constant, despite changes in their reflected light due to changing illumination. Although colour constancy has evolved under a constrained subset of illuminations, it is unknown whether its underlying mechanisms, thought to involve multiple components from retina to cortex, are optimised for particular environmental variations. Here we demonstrate a new method for investigating colour constancy using illumination matching in real scenes which, unlike previous methods using surface matching and simulated scenes, allows testing of multiple, real illuminations. We use real scenes consisting of solid familiar or unfamiliar objects against uniform or variegated backgrounds and compare discrimination performance for typical illuminations from the daylight chromaticity locus (approximately blue-yellow and atypical spectra from an orthogonal locus (approximately red-green, at correlated colour temperature 6700 K, all produced in real time by a 10-channel LED illuminator. We find that discrimination of illumination changes is poorer along the daylight locus than the atypical locus, and is poorest particularly for bluer illumination changes, demonstrating conversely that surface colour constancy is best for blue daylight illuminations. Illumination discrimination is also enhanced, and therefore colour constancy diminished, for uniform backgrounds, irrespective of the object type. These results are not explained by statistical properties of the scene signal changes at the retinal level. We conclude that high-level mechanisms of colour constancy are biased for the blue daylight illuminations and variegated backgrounds to which the human visual system has typically been exposed.

  1. Auditory imagery: empirical findings.

    Science.gov (United States)

    Hubbard, Timothy L

    2010-03-01

    The empirical literature on auditory imagery is reviewed. Data on (a) imagery for auditory features (pitch, timbre, loudness), (b) imagery for complex nonverbal auditory stimuli (musical contour, melody, harmony, tempo, notational audiation, environmental sounds), (c) imagery for verbal stimuli (speech, text, in dreams, interior monologue), (d) auditory imagery's relationship to perception and memory (detection, encoding, recall, mnemonic properties, phonological loop), and (e) individual differences in auditory imagery (in vividness, musical ability and experience, synesthesia, musical hallucinosis, schizophrenia, amusia) are considered. It is concluded that auditory imagery (a) preserves many structural and temporal properties of auditory stimuli, (b) can facilitate auditory discrimination but interfere with auditory detection, (c) involves many of the same brain areas as auditory perception, (d) is often but not necessarily influenced by subvocalization, (e) involves semantically interpreted information and expectancies, (f) involves depictive components and descriptive components, (g) can function as a mnemonic but is distinct from rehearsal, and (h) is related to musical ability and experience (although the mechanisms of that relationship are not clear). PMID:20192565

  2. Colour constancy across the life span: evidence for compensatory mechanisms.

    Science.gov (United States)

    Wuerger, Sophie

    2013-01-01

    It is well known that the peripheral visual system declines with age: the yellowing of the lens causes a selective reduction of short-wavelength light and sensitivity losses occur in the cone receptor mechanisms. At the same time, our subjective experience of colour does not change with age. The main purpose of this large-scale study (n = 185) covering a wide age range of colour-normal observers (18-75 years of age) was to assess the extent to which the human visual system is able to compensate for the changes in the optical media and at which level of processing this compensation is likely to occur. We report two main results: (1) Supra-threshold parafoveal colour perception remains largely unaffected by the age-related changes in the optical media (yellowing of the lens) whereas our ability to discriminate between small colour differences is compromised with an increase in age. (2) Significant changes in colour appearance are only found for unique green settings under daylight viewing condition which is consistent with the idea that the yellow-blue mechanism is most affected by an increase in age due to selective attenuation of short-wavelength light. The data on the invariance of hue perception, in conjunction with the age-related decline in chromatic sensitivity, provides evidence for compensatory mechanisms that enable colour-normal human observers a large degree of colour constancy across the life span. These compensatory mechanisms are likely to originate at cortical sites. PMID:23667689

  3. Colour constancy across the life span: evidence for compensatory mechanisms.

    Science.gov (United States)

    Wuerger, Sophie

    2013-01-01

    It is well known that the peripheral visual system declines with age: the yellowing of the lens causes a selective reduction of short-wavelength light and sensitivity losses occur in the cone receptor mechanisms. At the same time, our subjective experience of colour does not change with age. The main purpose of this large-scale study (n = 185) covering a wide age range of colour-normal observers (18-75 years of age) was to assess the extent to which the human visual system is able to compensate for the changes in the optical media and at which level of processing this compensation is likely to occur. We report two main results: (1) Supra-threshold parafoveal colour perception remains largely unaffected by the age-related changes in the optical media (yellowing of the lens) whereas our ability to discriminate between small colour differences is compromised with an increase in age. (2) Significant changes in colour appearance are only found for unique green settings under daylight viewing condition which is consistent with the idea that the yellow-blue mechanism is most affected by an increase in age due to selective attenuation of short-wavelength light. The data on the invariance of hue perception, in conjunction with the age-related decline in chromatic sensitivity, provides evidence for compensatory mechanisms that enable colour-normal human observers a large degree of colour constancy across the life span. These compensatory mechanisms are likely to originate at cortical sites.

  4. Perceptual constancy in judgments of egocentric distance: prevailing binocular information

    Directory of Open Access Journals (Sweden)

    Matsushima Elton H.

    2003-01-01

    Full Text Available Binocular cues were considered the prevailing information on specifying depth since the beginning of vision research. In the present study, two perceptual responses, the classical verbal report and a more recent method, open-loop walking, were used to assess the role of binocular information for egocentric distance perception. In two cue conditions environments, full- and reduced-cue, observers judged and walked egocentric distances of stimuli presented at eye-level, under binocular or monocular viewing. Results indicated perceptual constancy for open-loop walking and binocular responses, as well as poor performances under strong degradation on visual information (reduced-cue under monocular viewing, thus presenting evidence to support the fundamental role of binocular information on perception of egocentric distances. Besides that, visually directed actions could be adequate measures of perceived distance, with a better reliability than verbal report, since they were quite free of intrusion of inferential processes and perceptual tendencies. In addition, reduced head movements, side-to-side as well as back and forth deflexion movements, could have contributed to a near perfect coupling between binocular disparity information and open-loop walking responses.

  5. Tritium and helium-3 studies in Lake Constance

    International Nuclear Information System (INIS)

    From the experimental work at present available, a qualitative understanding of the processes of gas exchange with the atmosphere and of internal mixing of the water of large lakes can be derived. A quantitative treatment of these processes and of the parameters governing them still lags behind considerably, because of experimental and methodological difficulties. The dynamic response of a large lake to changes in its environmental conditions is thus far from being predictable. It is evident, on the other hand, that besides biological/chemical processes the physical processes in question play an important role in the budgets of many substances dissolved in the lake water, e.g. CO2, O2 and phosphorus. One approach to a better understanding of these processes is the use of geochemical tracers that are present in natural lakes, e.g. deuterium, oxygen-18, tritium, helium-3 and radon-222. This present communication is a status report of a continuing study being carried out in Lake Constance, Federal Republic of Germany. Bomb tritium and its decay product helium-3 as well as radon-222 have been used in this study. The results of the tritium and the helium-3 will be discussed here

  6. The CONSTANCES cohort, an epidemiological research infrastructure. Methods and results of the pilot phase

    Directory of Open Access Journals (Sweden)

    Marie Zins

    2013-06-01

    Full Text Available Background: prospective cohorts represent an essential design for epidemiological studies and allow for the study of the combined effects of lifestyle, environment, genetic predisposition, and other risk factors on a large variety of disease endpoints. The CONSTANCES cohort is intended to provide public health information and to serve as an epidemiological research infrastructure accessible to the epidemiologic research community. Although designed as a “general-purpose” cohort with very broad coverage, it will particularly focus on occupational and social determinants of health, and on chronic diseases and aging.Methods: the CON STANC ES cohort is designed as a randomly selected representative sample of French adults aged 18-69 years at inception; 200 000 subjects will be included over a five-year period. At inclusion, the selected subjects are invited to fill a questionnaire and to attend a Health Screening Center (HSC for a comprehensive health examination: weight, height, blood pressure, electrocardiogram, vision, auditory, spirometry, and biological parameters; for those aged 45 years and older, a specific work-up of functional, physical, and cognitive capacities is performed. A biobank will be set up. The follow-up includes a yearly self-administered questionnaire, and a periodic visit to an HSC. Social and work-related events and health data are collected from the French national retirement, health and death databases. The data include social and demographic characteristics, socioeconomic status, life events, behaviors, and occupational factors. The health data cover a wide spectrum: self-reported health scales, reported prevalent and incident diseases, long-term chronic diseases and hospitalizations, sick-leaves, handicaps, limitations, disabilities and injuries, healthcare utilization and services provided, and causes of death. To take into account non-participation at inclusion and attrition throughout the longitudinal follow-up, a

  7. Color-induced graph colorings

    CERN Document Server

    Zhang, Ping

    2015-01-01

    A comprehensive treatment of color-induced graph colorings is presented in this book, emphasizing vertex colorings induced by edge colorings. The coloring concepts described in this book depend not only on the property required of the initial edge coloring and the kind of objects serving as colors, but also on the property demanded of the vertex coloring produced. For each edge coloring introduced, background for the concept is provided, followed by a presentation of results and open questions dealing with this topic. While the edge colorings discussed can be either proper or unrestricted, the resulting vertex colorings are either proper colorings or rainbow colorings. This gives rise to a discussion of irregular colorings, strong colorings, modular colorings, edge-graceful colorings, twin edge colorings and binomial colorings. Since many of the concepts described in this book are relatively recent, the audience for this book is primarily mathematicians interested in learning some new areas of graph colorings...

  8. Colour constancy across the life span: evidence for compensatory mechanisms.

    Directory of Open Access Journals (Sweden)

    Sophie Wuerger

    Full Text Available It is well known that the peripheral visual system declines with age: the yellowing of the lens causes a selective reduction of short-wavelength light and sensitivity losses occur in the cone receptor mechanisms. At the same time, our subjective experience of colour does not change with age. The main purpose of this large-scale study (n = 185 covering a wide age range of colour-normal observers (18-75 years of age was to assess the extent to which the human visual system is able to compensate for the changes in the optical media and at which level of processing this compensation is likely to occur. We report two main results: (1 Supra-threshold parafoveal colour perception remains largely unaffected by the age-related changes in the optical media (yellowing of the lens whereas our ability to discriminate between small colour differences is compromised with an increase in age. (2 Significant changes in colour appearance are only found for unique green settings under daylight viewing condition which is consistent with the idea that the yellow-blue mechanism is most affected by an increase in age due to selective attenuation of short-wavelength light. The data on the invariance of hue perception, in conjunction with the age-related decline in chromatic sensitivity, provides evidence for compensatory mechanisms that enable colour-normal human observers a large degree of colour constancy across the life span. These compensatory mechanisms are likely to originate at cortical sites.

  9. Determination of Sectional Constancy of Organic Coal-Water Fuel Compositions

    Science.gov (United States)

    Dmitrienko, Margarita A.; Nyashina, Galina S.; Strizhak, Pavel A.

    2016-02-01

    To use widespreadly the waste of coals and oils processing in the great and the small-scale power generation, the key parameter, which is sectional constancy of promising organic coal-water fuels (OCWF), was studied. The compo-sitions of OCWF from brown and bituminous coals, filter cakes, used motor, turbine and dielectrical oils, water-oil emul-sion and special wetting agent (plasticizer) were investigated. Two modes of preparation were considered. They are with homogenizer and cavitator. It was established that the constancy did not exceed 5-7 days for the compositions of OCWF with brown coals, and 12-15 days for that compositions with bituminous coals and filter cakes. The injection of used oils in a composition of OCWF led to increase in viscosity of fuel compositions and their sectional constancy.

  10. A new colour constancy algorithm based on automatic determination of gray framework parameters using neural network

    Indian Academy of Sciences (India)

    Mohammad Mehdi Faghih; Zeynab Khosravinia; Mohsen Ebrahimi Moghaddam

    2014-04-01

    Colour constancy is defined as the ability to estimate the actual colours of objects in an acquired image disregarding the colour of scene illuminant. Despite large variety of existing methods, no colour constancy algorithm can be considered as universal. Among the methods, the gray framework is one of the best-known and most used approaches. This framework has some parameters that should be set with appropriate values to achieve the best performance for each image. In this article, we propose a neural network-based algorithm that aims to automatically determine the best value of gray framework parameters for each image. It is a multi-level approach that estimates the optimal values for the gray framework parameters based on relevant features extracted from the input image. Experimental results on two popular colour constancy datasets show an acceptable improvement over state-of-the-art methods.

  11. Auditory-motor learning influences auditory memory for music.

    Science.gov (United States)

    Brown, Rachel M; Palmer, Caroline

    2012-05-01

    In two experiments, we investigated how auditory-motor learning influences performers' memory for music. Skilled pianists learned novel melodies in four conditions: auditory only (listening), motor only (performing without sound), strongly coupled auditory-motor (normal performance), and weakly coupled auditory-motor (performing along with auditory recordings). Pianists' recognition of the learned melodies was better following auditory-only or auditory-motor (weakly coupled and strongly coupled) learning than following motor-only learning, and better following strongly coupled auditory-motor learning than following auditory-only learning. Auditory and motor imagery abilities modulated the learning effects: Pianists with high auditory imagery scores had better recognition following motor-only learning, suggesting that auditory imagery compensated for missing auditory feedback at the learning stage. Experiment 2 replicated the findings of Experiment 1 with melodies that contained greater variation in acoustic features. Melodies that were slower and less variable in tempo and intensity were remembered better following weakly coupled auditory-motor learning. These findings suggest that motor learning can aid performers' auditory recognition of music beyond auditory learning alone, and that motor learning is influenced by individual abilities in mental imagery and by variation in acoustic features. PMID:22271265

  12. Color Homography

    OpenAIRE

    Finlayson, Graham; Gong, Han; Fisher, Robert

    2016-01-01

    We show the surprising result that colors across a change in viewing condition (changing light color, shading and camera) are related by a homography. Our homography color correction application delivers improved color fidelity compared with the linear least-square.

  13. Color Blindness

    Science.gov (United States)

    ... rose in full bloom. If you have a color vision defect, you may see these colors differently than most people. There are three main kinds of color vision defects. Red-green color vision defects are the ...

  14. Constancy check of beam quality in conventional diagnostic X-ray equipment

    International Nuclear Information System (INIS)

    A tandem ionization chamber was developed for quality control programs of X-ray equipment used in conventional radiography and mammography. A methodology for the use of the tandem chamber in the constancy check of diagnostic X-ray beam qualities was established. The application at a medical X-ray imaging facility of this established methodology is presented. The use of the tandem chamber in the constancy check of diagnostic X-ray beam qualities is a useful method to control the performance of the X-ray equipment

  15. Discrimination of cone contrast changes as evidence for colour constancy in cerebral achromatopsia.

    Science.gov (United States)

    Hurlbert, A C; Bramwell, D I; Heywood, C; Cowey, A

    1998-11-01

    One proposed mechanism for underpinning colour constancy is computation of the relative activity of cones within one class--cone ratios, or cone contrasts--between surfaces in a fixed scene undergoing a change in illuminant. Although there is evidence that cone ratios do determine colour appearance under many conditions, the site or sites of their computation is unknown. Here, we report that a cerebrally achromatopsic observer, MS, displayed evidence of colour constancy in asymmetric colour matching tasks and was able to discriminate changes in cone ratios for simple, but not complex scenes. We hypothesise that the site of local cone-ratio computation is therefore early in the visual system, probably retinal.

  16. Experimental results from the Constance B magnetic mirror. Progress report, October 1983-June 1986

    International Nuclear Information System (INIS)

    In this report the Constance B mirror facility at the Massachusetts Institute of Technology is described and the experimental research which has been carried out from October 1983 through June 1986 is summarized. Constance B is a plasma confinement device of the quadrupole, or minimum-B, magnetic mirror geometry. Electron cyclotron resonance heating (ECRH) is used to create and heat high beta (beta = plasma pressure/magnetic field pressure), hot electron plasmas for thermonuclear fusion research. The typical operating parameters achieved in the machine are shown

  17. Color and polarization vision in foraging Papilio.

    Science.gov (United States)

    Kinoshita, Michiyo; Arikawa, Kentaro

    2014-06-01

    This paper gives an overview of behavioral studies on the color and polarization vision of the Japanese yellow swallowtail butterfly, Papilio xuthus. We focus on indoor experiments on foraging individuals. Butterflies trained to visit a disk of certain color correctly select that color among various other colors and/or shades of gray. Correct selection persists under colored illumination, but is systematically shifted by background colors, indicating color constancy and simultaneous color contrast. While their eyes contain six classes of spectral receptors, their wavelength discrimination performance indicates that their color vision is tetrachromatic. P. xuthus innately prefers brighter targets, but can be trained to select dimmer ones under certain conditions. Butterflies trained to a dark red stimulus select an orange disk presented on a bright gray background over one on dark gray. The former probably appears darker to them, indicating brightness contrast. P. xuthus has a strong innate preference for vertically polarized light, but the selection of polarized light changes depending on the intensity of simultaneously presented unpolarized light. Discrimination of polarization also depends on background intensity. Similarities between brightness and polarization vision suggest that P. xuthus perceive polarization angle as brightness, such that vertical polarization appears brighter than horizontal polarization.

  18. Chronologie de la vie et des œuvres de Constance Fenimore Woolson Chronology of Constance Fenimore Woolson’s Life and Work

    Directory of Open Access Journals (Sweden)

    Jeannine Hayat

    2007-01-01

    Full Text Available Français1840Constance Fenimore Woolson est née à Claremont, New Hampshire (5 mars. Elle était le sixième enfant de Charles Jarvis et de Hannah Cooper Pomeroy Woolson. Elle était, par sa mère, une petite-nièce de James Fenimore Cooper.Automne 1840Les Woolson déménagent à Cleveland, Ohio, après le décès de trois de leurs filles, atteintes de la scarlatine. Enfant et jeune fille, Constance voyage en Ohio, dans le Wisconsin et en Nouvelle Angleterre.Eté 1855Elle découvre l’île de Mackinac dans l...

  19. Global color and albedo variations on Io

    Science.gov (United States)

    Mcewen, Alfred S.

    1988-01-01

    The present Voyager imaging data multispectral mosaics of Io include global mosaics from each of the Voyager 1 and 2 data sets and a high-resolution mosaic of the region centered on the Ra Patera volcano. The constancy of the disk-integrated color and albedo of Io over recent decades despite volcanic activity may be due to the regular occurrence of large Pele-type plumes with relatively dark, red deposits. Io's intrinsic spectral variability involves continuous variation among three major spectral end members. Attention is given to the mapping of the data into five spectral units for the purposes of comparison with laboratory measurements of Io surface material candidates.

  20. Illuminant spectrum estimation using a digital color camera and a color chart

    Science.gov (United States)

    Shi, Junsheng; Yu, Hongfei; Huang, Xiaoqiao; Chen, Zaiqing; Tai, Yonghang

    2014-10-01

    Illumination estimation is the main step in color constancy processing, also an important prerequisite for digital color image reproduction and many computer vision applications. In this paper, a method for estimating illuminant spectrum is investigated using a digital color camera and a color chart under the situation when the spectral reflectance of the chart is known. The method is based on measuring CIEXYZ of the chart using the camera. The first step of the method is to gain camera's color correction matrix and gamma values by taking a photo of the chart under a standard illuminant. The second step is to take a photo of the chart under an estimated illuminant, and the camera's inherent RGB values are converted to the standard sRGB values and further converted to CIEXYZ of the chart. Based on measured CIEXYZ and known spectral reflectance of the chart, the spectral power distribution (SPD) of the illuminant is estimated using the Wiener estimation and smoothing estimation. To evaluate the performance of the method quantitatively, the goodnessfitting coefficient (GFC) was used to measure the spectral match and the CIELAB color difference metric was used to evaluate the color match between color patches under the estimated and actual SPDs. The simulated experiment was carried to estimate CIE standard illuminant D50 and C using X-rite ColorChecker 24-color chart, the actual experiment was carried to estimate daylight and illuminant A using two consumergrade cameras and the chart, and the experiment results verified feasible of the investigated method.

  1. Auditory Responses of Infants

    Science.gov (United States)

    Watrous, Betty Springer; And Others

    1975-01-01

    Forty infants, 3- to 12-months-old, participated in a study designed to differentiate the auditory response characteristics of normally developing infants in the age ranges 3 - 5 months, 6 - 8 months, and 9 - 12 months. (Author)

  2. The Development of Language Constancy: Attention to Native versus Nonnative Accents

    Science.gov (United States)

    Kitamura, Christine; Panneton, Robin; Best, Catherine T.

    2013-01-01

    The time frame for infants' acquisition of language constancy was probed, using the phonetic variation in a rarely heard accent (South African English) or a frequently heard accent (American English). A total of 156 Australian infants were tested. Six-month-olds looked longer to Australian English than less commonly heard South African…

  3. Morphological Constancy in Spelling: A Comparison of Children with Dyslexia and Typically Developing Children

    Science.gov (United States)

    Bourassa, Derrick C.; Treiman, Rebecca

    2008-01-01

    The spellings of many English words follow a principle of morphological constancy. For example, "musician" includes the c of "music", even though the pronunciation of this letter changes. With other words, such as "explanation" and "explain", the spellings of morphemes are not retained when affixes are added. We asked whether children with…

  4. Relativistic addition of perpendicular velocity components from the constancy of the speed of light

    OpenAIRE

    Hu, Ben Yu-Kuang

    2006-01-01

    Mermin [Am. J. Phys. {\\bf 51}, 1130--1131 (1983)] derived the relativistic addition of the parallel components of velocity using the constancy of the speed of light. In this note, the derivation is extended to the perpendicular components of velocity.

  5. Revisiting the Principle of Relative Constancy: Consumer Mass Media Expenditures in Belgium.

    Science.gov (United States)

    Dupagne, Michel; Green, R. Jeffery

    1996-01-01

    Proposes two new econometric models for testing the principle of relative constancy (PRC). Reports on regression and cointegration analyses conducted with Belgian mass media expenditure data from 1953-91. Suggests that alternative mass media expenditure models should be developed because PRC lacks of economic foundation and sound empirical…

  6. Spatial and temporal aspects of chromatic adaptation and their functional significance for colour constancy.

    Science.gov (United States)

    Werner, Annette

    2014-11-01

    Illumination in natural scenes changes at multiple temporal and spatial scales: slow changes in global illumination occur in the course of a day, and we encounter fast and localised illumination changes when visually exploring the non-uniform light field of three-dimensional scenes; in addition, very long-term chromatic variations may come from the environment, like for example seasonal changes. In this context, I consider the temporal and spatial properties of chromatic adaptation and discuss their functional significance for colour constancy in three-dimensional scenes. A process of fast spatial tuning in chromatic adaptation is proposed as a possible sensory mechanism for linking colour constancy to the spatial structure of a scene. The observed middlewavelength selectivity of this process is particularly suitable for adaptation to the mean chromaticity and the compensation of interreflections in natural scenes. Two types of sensory colour constancy are distinguished, based on the functional differences of their temporal and spatial scales: a slow type, operating at a global scale for the compensation of the ambient illumination; and a fast colour constancy, which is locally restricted and well suited to compensate region-specific variations in the light field of three dimensional scenes. PMID:25449338

  7. [Central auditory prosthesis].

    Science.gov (United States)

    Lenarz, T; Lim, H; Joseph, G; Reuter, G; Lenarz, M

    2009-06-01

    Deaf patients with severe sensory hearing loss can benefit from a cochlear implant (CI), which stimulates the auditory nerve fibers. However, patients who do not have an intact auditory nerve cannot benefit from a CI. The majority of these patients are neurofibromatosis type 2 (NF2) patients who developed neural deafness due to growth or surgical removal of a bilateral acoustic neuroma. The only current solution is the auditory brainstem implant (ABI), which stimulates the surface of the cochlear nucleus in the brainstem. Although the ABI provides improvement in environmental awareness and lip-reading capabilities, only a few NF2 patients have achieved some limited open set speech perception. In the search for alternative procedures our research group in collaboration with Cochlear Ltd. (Australia) developed a human prototype auditory midbrain implant (AMI), which is designed to electrically stimulate the inferior colliculus (IC). The IC has the potential as a new target for an auditory prosthesis as it provides access to neural projections necessary for speech perception as well as a systematic map of spectral information. In this paper the present status of research and development in the field of central auditory prostheses is presented with respect to technology, surgical technique and hearing results as well as the background concepts of ABI and AMI. PMID:19517084

  8. The reliability and validity of Turkish Form of the Gender Constancy ScaleThe reliability and validity of Turkish Form of the Gender Constancy Scale

    Directory of Open Access Journals (Sweden)

    Rengin Zembat

    2012-02-01

    Full Text Available Extended AbstractRationale of the study: Gender has been a (research interest for social psychology as it investigates people's social lives and every aspect of their social behaviors; and for educational sciences because of classification period and its relationship with social learning (Dökmen, 2004, s.31. For this reason, there are a lot of different approaches (psychoanalytic theory, social learning theory, cognitive development theory and gender schema theory trying to clarify the context and the development of gender and the variables it is related to. Kohlberg's views are referred to be the first ones that presented a cognitive approach while explaining gender development and cognitive development theory is acknowledged as the most effective judgment (Bem, 1989; Szkrybalo, 1998. Kohlberg suggested that gender development follows three sequential stages. These are gender identity/ labeling, gender stability over time and gender consistency across situations. A child who reached third stage, gender consistency across situations is identified to have gender constancy (Hollander, 2001. The purpose of the study: The aim of this research is to do linguistic equivalency, validity-reliability studies of Gender Constancy Scale (2004 which is reorganized according to the stages of acquiring gender constancy suggested by Kohlberg, based on cognitive development theory.Method: In this study, survey method was used. Gender Constancy Scale was used for data collection. The instrument was formed by using the items of the validated scales developed by Frey and Taylor, Slaby and Frey and Emmerich et. al. The original form of the scale is in English. The scale has fours sub-scales: Identity, Stability, Motivation and Consistency. The levels of motivation and consistency consist of close – ended and open – ended interview items. Firstly, the linguistic equivalence studies of the instrument were done and then, individual administrations were conducted

  9. Efficient color representation for image segmentation under nonwhite illumination

    Science.gov (United States)

    Park, Jae Byung

    2003-10-01

    Color image segmentation algorithms often consider object color to be a constant property of an object. If the light source dominantly exhibits a particular color, however, it becomes necessary to consider the color variation induced by the colored illuminant. This paper presents a new approach to segmenting color images that are photographed under non-white illumination conditions. It also addresses how to estimate the color of illuminant in terms of the standard RGB color values rather than the spectrum of the illuminant. With respect to the illumination axis that goes through the origin and the centroid of illuminant color clusters (prior given by the estimation process), the RGB color space is transformed into our new color coordinate system. Our new color scheme shares the intuitiveness of the HSI (HSL or HSV) space that comes from the conical (double-conical or cylindrical) structure of hue and saturation aligned with the intensity variation at its center. It has been developed by locating the ordinary RGB cube in such a way that the illumination axis aligns with the vertical axis (Z-axis) of a larger Cartesian (XYZ) space. The work in this paper uses the dichromatic reflection model [1] to interpret the physics about light and optical effects in color images. The linearity proposed in the dichromatic reflection model is essential and is well preserved in the RGB color space. By proposing a straightforward color model transduction, we suggest dimensionality reduction and provide an efficient way to analyze color images of dielectric objects under non-white illumination conditions. The feasibility of the proposed color representation has been demonstrated by our experiment that is twofold: 1) Segmentation result from a multi-modal histogram-based thresholding technique and 2) Color constancy result from discounting illumination effect further by color balancing.

  10. Auditory and Visual Sensations

    CERN Document Server

    Ando, Yoichi

    2010-01-01

    Professor Yoichi Ando, acoustic architectural designer of the Kirishima International Concert Hall in Japan, presents a comprehensive rational-scientific approach to designing performance spaces. His theory is based on systematic psychoacoustical observations of spatial hearing and listener preferences, whose neuronal correlates are observed in the neurophysiology of the human brain. A correlation-based model of neuronal signal processing in the central auditory system is proposed in which temporal sensations (pitch, timbre, loudness, duration) are represented by an internal autocorrelation representation, and spatial sensations (sound location, size, diffuseness related to envelopment) are represented by an internal interaural crosscorrelation function. Together these two internal central auditory representations account for the basic auditory qualities that are relevant for listening to music and speech in indoor performance spaces. Observed psychological and neurophysiological commonalities between auditor...

  11. Color blindness

    Science.gov (United States)

    ... color blindness often have problems seeing reds and greens, too. The most severe form of color blindness is achromatopsia. This is a rare condition in which a person cannot see any color, only shades of gray. Most color blindness is due to ...

  12. Color Blindness

    Institute of Scientific and Technical Information of China (English)

    严双红

    2007-01-01

    About one in 12 boys is color-blind, and one in every 400 girls, so in each school class there are likely to be at least one or two people who are color-blind. Because they are color- blind from birth, most people do not know that they are color-

  13. Auditory spatial perception dynamically realigns with changing eye position.

    Science.gov (United States)

    Razavi, Babak; O'Neill, William E; Paige, Gary D

    2007-09-19

    Audition and vision both form spatial maps of the environment in the brain, and their congruency requires alignment and calibration. Because audition is referenced to the head and vision is referenced to movable eyes, the brain must accurately account for eye position to maintain alignment between the two modalities as well as perceptual space constancy. Changes in eye position are known to variably, but inconsistently, shift sound localization, suggesting subtle shortcomings in the accuracy or use of eye position signals. We systematically and directly quantified sound localization across a broad spatial range and over time after changes in eye position. A sustained fixation task addressed the spatial (steady-state) attributes of eye position-dependent effects on sound localization. Subjects continuously fixated visual reference spots straight ahead (center), to the left (20 degrees), or to the right (20 degrees) of the midline in separate sessions while localizing auditory targets using a laser pointer guided by peripheral vision. An alternating fixation task focused on the temporal (dynamic) aspects of auditory spatial shifts after changes in eye position. Localization proceeded as in sustained fixation, except that eye position alternated between the three fixation references over multiple epochs, each lasting minutes. Auditory space shifted by approximately 40% toward the new eye position and dynamically over several minutes. We propose that this spatial shift reflects an adaptation mechanism for aligning the "straight-ahead" of perceived sensory-motor maps, particularly during early childhood when normal ocular alignment is achieved, but also resolving challenges to normal spatial perception throughout life. PMID:17881531

  14. The effect of memory and context changes on color matches to real objects.

    Science.gov (United States)

    Allred, Sarah R; Olkkonen, Maria

    2015-07-01

    Real-world color identification tasks often require matching the color of objects between contexts and after a temporal delay, thus placing demands on both perceptual and memory processes. Although the mechanisms of matching colors between different contexts have been widely studied under the rubric of color constancy, little research has investigated the role of long-term memory in such tasks or how memory interacts with color constancy. To investigate this relationship, observers made color matches to real study objects that spanned color space, and we independently manipulated the illumination impinging on the objects, the surfaces in which objects were embedded, and the delay between seeing the study object and selecting its color match. Adding a 10-min delay increased both the bias and variability of color matches compared to a baseline condition. These memory errors were well accounted for by modeling memory as a noisy but unbiased version of perception constrained by the matching methods. Surprisingly, we did not observe significant increases in errors when illumination and surround changes were added to the 10-minute delay, although the context changes alone did elicit significant errors. PMID:25824887

  15. Activity and Diversity of Methanotrophic Bacteria at Methane Seeps in Eastern Lake Constance Sediments ▿

    OpenAIRE

    Deutzmann, Jörg; Wörner, Susanne; Schink, Bernhard

    2011-01-01

    The activity and community structure of aerobic methanotrophic communities were investigated at methane seeps (pockmarks) in the littoral and profundal zones of an oligotrophic freshwater lake (Lake Constance, Germany). Measurements of potential methane oxidation rates showed that sediments inside littoral pockmarks are hot spots of methane oxidation. Potential methane oxidation rates at littoral pockmark sites exceeded the rates of the surrounding sediment by 2 orders of magnitude. Terminal ...

  16. The Constance B mirror as a source of highly stripped ions

    International Nuclear Information System (INIS)

    The potential of the Constance B mirror as a source of highly stripped ions for fundamental atomic physics research is described. The hot electron, cold ion plasma (ntau > 2 x 1011 cm-3-s, T/sub eh/=400 keV, T/sub i/ -8 torr during the decay of the hot electrons. A 28 GHz upgrade machine in which Xe+50 could be produced, is also described

  17. Hearing colors: An example of Brain Plasticity

    OpenAIRE

    ARANTXA eALFARO; Angela eBernabeu; Carlos eAgullo; Jaime eParra; Eduardo eFernandez

    2015-01-01

    Sensory substitution devices are providing new ways for improving or replacing sensory abilities that have been lost due to disease or injury, and at the same time offer unprecedented opportunities to address how the nervous system could lead to an augmentation of its capacities. In this work we have evaluated a color-blind subject using a new visual-to-auditory sensory substitution device (SSD) device called Eyeborg, that allows colors to be perceived as sounds. We used a combination of neur...

  18. The neglected neglect: auditory neglect.

    Science.gov (United States)

    Gokhale, Sankalp; Lahoti, Sourabh; Caplan, Louis R

    2013-08-01

    Whereas visual and somatosensory forms of neglect are commonly recognized by clinicians, auditory neglect is often not assessed and therefore neglected. The auditory cortical processing system can be functionally classified into 2 distinct pathways. These 2 distinct functional pathways deal with recognition of sound ("what" pathway) and the directional attributes of the sound ("where" pathway). Lesions of higher auditory pathways produce distinct clinical features. Clinical bedside evaluation of auditory neglect is often difficult because of coexisting neurological deficits and the binaural nature of auditory inputs. In addition, auditory neglect and auditory extinction may show varying degrees of overlap, which makes the assessment even harder. Shielding one ear from the other as well as separating the ear from space is therefore critical for accurate assessment of auditory neglect. This can be achieved by use of specialized auditory tests (dichotic tasks and sound localization tests) for accurate interpretation of deficits. Herein, we have reviewed auditory neglect with an emphasis on the functional anatomy, clinical evaluation, and basic principles of specialized auditory tests.

  19. Uncalibrated color

    Science.gov (United States)

    Moroney, Nathan

    2006-01-01

    Color calibration or the use of color measurement processes to characterize the color properties of a device or workflow is often expected or assumed for many color reproduction applications. However it is interesting to consider applications or situations in which color calibration is not as critical. In the first case it is possible to imagine an implicit color calibration resulting from a standardization or convergence of the colorant and substrate spectrum. In the second case it is possible to imagine cases where the device color variability is significantly less than the user color thresholds or expectations for color consistency. There are still general requirements for this form of pragmatic color but they are generally lower than for the higher end of digital color reproduction. Finally it is possible to imagine an implicit calibration that leverages in some way the highly accurate memory color for the hue of common objects. This scenario culminates with a challenge to create a natural capture calibration standard that does not require individual calibration, is spectrally diverse, is inexpensive and is environmentally friendly.

  20. Auditory pathways: anatomy and physiology.

    Science.gov (United States)

    Pickles, James O

    2015-01-01

    This chapter outlines the anatomy and physiology of the auditory pathways. After a brief analysis of the external, middle ears, and cochlea, the responses of auditory nerve fibers are described. The central nervous system is analyzed in more detail. A scheme is provided to help understand the complex and multiple auditory pathways running through the brainstem. The multiple pathways are based on the need to preserve accurate timing while extracting complex spectral patterns in the auditory input. The auditory nerve fibers branch to give two pathways, a ventral sound-localizing stream, and a dorsal mainly pattern recognition stream, which innervate the different divisions of the cochlear nucleus. The outputs of the two streams, with their two types of analysis, are progressively combined in the inferior colliculus and onwards, to produce the representation of what can be called the "auditory objects" in the external world. The progressive extraction of critical features in the auditory stimulus in the different levels of the central auditory system, from cochlear nucleus to auditory cortex, is described. In addition, the auditory centrifugal system, running from cortex in multiple stages to the organ of Corti of the cochlea, is described.

  1. Visual–auditory spatial processing in auditory cortical neurons

    OpenAIRE

    Bizley, Jennifer K.; King, Andrew J

    2008-01-01

    Neurons responsive to visual stimulation have now been described in the auditory cortex of various species, but their functions are largely unknown. Here we investigate the auditory and visual spatial sensitivity of neurons recorded in 5 different primary and non-primary auditory cortical areas of the ferret. We quantified the spatial tuning of neurons by measuring the responses to stimuli presented across a range of azimuthal positions and calculating the mutual information (MI) between the ...

  2. Ocean Color

    Data.gov (United States)

    National Aeronautics and Space Administration — Satellite-derived Ocean Color Data sets from historical and currently operational NASA and International Satellite missions including the NASA Coastal Zone Color...

  3. Resizing Auditory Communities

    DEFF Research Database (Denmark)

    Kreutzfeldt, Jacob

    2012-01-01

    Heard through the ears of the Canadian composer and music teacher R. Murray Schafer the ideal auditory community had the shape of a village. Schafer’s work with the World Soundscape Project in the 70s represent an attempt to interpret contemporary environments through musical and auditory...... of sound as an active component in shaping urban environments. As urban conditions spreads globally, new scales, shapes and forms of communities appear and call for new distinctions and models in the study and representation of sonic environments. Particularly so, since urban environments are increasingly...... presents some terminologies for mapping urban environments through its sonic configuration. Such probing into the practices of acoustic territorialisation may direct attention to some of the conflicting and disharmonious interests defining public inclusive domains. The paper investigates the concept...

  4. Color Names

    OpenAIRE

    Benavente, Robert; Van De Weijer, Joost; Vanrell, Maria; Schmid, Cordelia; Baldrich, Ramon; Verbeek, Jakob; Larlus, Diane

    2012-01-01

    International audience Within a computer vision context color naming is the action of assigning linguistic color labels to pixels, regions or objects in images. Humans use color names routinely and seemingly without effort to describe the world around us. They have been primarily studied in the fields of visual psychology, anthropology and linguistics [17]. Color names are for example used in the context of image retrieval. A user might query an image search engine for "red cars". The syste...

  5. Color invariance

    NARCIS (Netherlands)

    J.M. Geusebroek; R. van den Boomgaard; A.W.M. Smeulders; H. Geerts

    2001-01-01

    This paper presents the measurement of colored object reflectance, under different, general assumptions regarding the imaging conditions. We exploit the Gaussian scale-space paradigm for color images to define a framework for the robust measurement of object reflectance from color images. Object ref

  6. A virtual auditory environment for investigating the auditory signal processing of realistic sounds

    DEFF Research Database (Denmark)

    Favrot, Sylvain Emmanuel; Buchholz, Jörg

    2008-01-01

    reverberation. The environment is based on the ODEON room acoustic simulation software to render the acoustical scene. ODEON outputs are processed using a combination of different order Ambisonic techniques to calculate multichannel room impulse responses (mRIR). Auralization is then obtained by the convolution....... Throughout the VAE development, special care was taken in order to achieve a realistic auditory percept and to avoid “artifacts” such as unnatural coloration. The performance of the VAE has been evaluated and optimized on a 29 loudspeaker setup using both objective and subjective measurement techniques....

  7. Color Categories and Color Appearance

    Science.gov (United States)

    Webster, Michael A.; Kay, Paul

    2012-01-01

    We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue-green boundary, to test whether chromatic differences across the boundary…

  8. Color Terms and Color Concepts

    Science.gov (United States)

    Davidoff, Jules

    2006-01-01

    In their lead articles, both Kowalski and Zimiles (2006) and O'Hanlon and Roberson (2006) declare a general relation between color term knowledge and the ability to conceptually represent color. Kowalski and Zimiles, in particular, argue for a priority for the conceptual representation in color term acquisition. The complexities of the interaction…

  9. Constance Pascal's Chagrins d'amour et psychoses (1935): a French psychiatrist's views on psychoanalysis.

    Science.gov (United States)

    Gordon, Felicia

    2015-03-01

    In 1935 Constance Pascal (1877-1937), France's first woman psychiatrist, published Chagrins d'amour et psychoses (The Sorrows of Love and Psychosis). My analysis of her monograph will consider: her major article leading up to Chagrins; Pascal's debts to her predecessors, particularly Morel and Kretschmer; her relationship to the French psychoanalytic movement; her co-option of psychoanalysis as a tool in her own therapeutic work with patients in the state psychiatric system; and her social/cultural interpretations of her woman patients. The literary and philosophic aspects of her work are emphasized as well as her contribution to French psychiatry.

  10. The synodial practices of the Council of Constance (1414-1418): Between symbol and trace

    OpenAIRE

    Provvidente, Sebastián

    2013-01-01

    The decree Haec Sancta approved by the Council of Constance at its 5th Session (6th April 1415) helped the Council fathers to put an end to the scandalous schism which since 1378 had divided the Latin Church between rival lines of claimants to the papal office. It did so by claiming and exercising an authority superior to that of the Pope in certain circumstances. However, the interpretation of this decree has been a source of disagreement between historians, theologians and canonists. It is ...

  11. Auditory and non-auditory effects of noise on health

    NARCIS (Netherlands)

    Basner, M.; Babisch, W.; Davis, A.; Brink, M.; Clark, C.; Janssen, S.A.; Stansfeld, S.

    2013-01-01

    Noise is pervasive in everyday life and can cause both auditory and non-auditory health eff ects. Noise-induced hearing loss remains highly prevalent in occupational settings, and is increasingly caused by social noise exposure (eg, through personal music players). Our understanding of molecular mec

  12. Color Analysis

    Science.gov (United States)

    Wrolstad, Ronald E.; Smith, Daniel E.

    Color, flavor, and texture are the three principal quality attributes that determine food acceptance, and color has a far greater influence on our judgment than most of us appreciate. We use color to determine if a banana is at our preferred ripeness level, and a discolored meat product can warn us that the product may be spoiled. The marketing departments of our food corporations know that, for their customers, the color must be "right." The University of California Davis scorecard for wine quality designates four points out of 20, or 20% of the total score, for color and appearance (1). Food scientists who establish quality control specifications for their product are very aware of the importance of color and appearance. While subjective visual assessment and use of visual color standards are still used in the food industry, instrumental color measurements are extensively employed. Objective measurement of color is desirable for both research and industrial applications, and the ruggedness, stability, and ease of use of today's color measurement instruments have resulted in their widespread adoption.

  13. Age-related changes in color appearance depend on unique-hue components

    Science.gov (United States)

    Okajima, Katsunori; Tsuchiya, Nao; Yamashita, Kazuyuki

    2002-06-01

    In order to compare color appearance as seen by elderly and young people, we conducted an experiment where the subjects responded to the color appearance of 75 color chips using a categorical color naming method and an elemental color scaling method. The results show that categorical color naming between elderly and young subjects is almost identical for most color chips, but there were significant differences in the elemental color scaling between the two age groups depending on unique-hue components. The differences in yellow and blue components between elderly and young subjects suggest that the neural mechanism of color vision in elderly people may over perform on constancy of color appearance so as to compensate for the age-related change of the human crystalline lens. In addition, the chromatic components in elderly subjects indicate higher values than those in young subjects for low saturation color chips, whereas the chromatic components in elderly subjects indicate lower values than those in young subjects when viewing high saturation color chips. These results show that the age-related changes of unique hue components strongly depend on saturation of colors, and suggest that the practical range of color appearance in elderly people is small in comparison with young people.

  14. Partial Epilepsy with Auditory Features

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-07-01

    Full Text Available The clinical characteristics of 53 sporadic (S cases of idiopathic partial epilepsy with auditory features (IPEAF were analyzed and compared to previously reported familial (F cases of autosomal dominant partial epilepsy with auditory features (ADPEAF in a study at the University of Bologna, Italy.

  15. Mes soixante ans y sus referentes políticos y literarios: las memorias en verso de Constance de Salm

    Directory of Open Access Journals (Sweden)

    Ángela Magdalena Romera Pintor

    2015-04-01

    Full Text Available This article studies Constance de Salm’s memoirs, published in 1833 and entitled Mes soixante ans. In her memoirs composed in verse the author recallsher feminist discourse in support of women’s rights, as she did all her life. We will unveil the political and literary references of the poetic discourse, which recalls the moresignificant events in France in a period of great change: from the end of the 18thcentury and through the early part of the 19thcentury. We will pay particular attention to the Empire period, with which Constance de Salm’s works have been consistently associated

  16. Color Portraits: From Color Picking to Interacting with Color

    OpenAIRE

    Jalal, Ghita; Maudet, Nolwenn; Mackay, Wendy E.

    2015-01-01

    Although ubiquitous, color pickers have remained largely unchanged for 25 years. Based on contextual interviews with artists and designers, we created the Color Portraits design space to characterize five key color manipulation activities: sampling and tweaking individual colors, manipulating color relationships, combining colors with other elements, revisiting previous color choices, and revealing a design process through color. We found similar color manipulation requirements with scientist...

  17. Modeling human color categorization: color discrimination and color memory

    OpenAIRE

    Broek, van den, M.M.P.; Hendriks, M.A.; Puts, M.J.H.; Heskes, T.; Lucas, P.; Vuurpijl, L.G.; W. Wiegerinck

    2003-01-01

    Color matching in Content-Based Image Retrieval is done using a color space and measuring distances between colors. Such an approach yields non-intuitive results for the user. We introduce color categories (or focal colors), determine that they are valid, and use them in two experiments. The experiments conducted prove the difference between color categorization by the cognitive processes color discrimination and color memory. In addition, they yield a Color Look-Up Table, which can improve c...

  18. The Perception of Auditory Motion.

    Science.gov (United States)

    Carlile, Simon; Leung, Johahn

    2016-01-01

    The growing availability of efficient and relatively inexpensive virtual auditory display technology has provided new research platforms to explore the perception of auditory motion. At the same time, deployment of these technologies in command and control as well as in entertainment roles is generating an increasing need to better understand the complex processes underlying auditory motion perception. This is a particularly challenging processing feat because it involves the rapid deconvolution of the relative change in the locations of sound sources produced by rotational and translations of the head in space (self-motion) to enable the perception of actual source motion. The fact that we perceive our auditory world to be stable despite almost continual movement of the head demonstrates the efficiency and effectiveness of this process. This review examines the acoustical basis of auditory motion perception and a wide range of psychophysical, electrophysiological, and cortical imaging studies that have probed the limits and possible mechanisms underlying this perception. PMID:27094029

  19. An evolutionary approach for colour constancy based on gamut mapping constraint satisfaction

    Indian Academy of Sciences (India)

    Shahin Sabooni; Mohsen Ebrahimi Moghaddam

    2013-08-01

    Many colour constancy algorithms have been proposed to achieve a good performance in this field. The gamut mapping algorithm is one of the most accurate and promising algorithms based on gamut assumption: illuminant can be estimated by comparing the colours distribution in the current image to acanonical gamut (i.e., a pre-learned distribution of colours). However, the gamut mapping algorithm is precise but it is time consuming. Therefore, some other methods such as GCIE (gamut constrained illuminant estimation) and CGM (cubical gamut mapping) have been proposed which work faster. However, the results of such methods are poor when the source light is not in the pre-defined ones. In this paper, we propose an evolutionary algorithm for colour constancy based on gamut mapping assumption. This approach overcomes the mentioned problem in other gamut-based methods. The proposed evolutionary method uses a simple chromosome structure together with simple operators such as mutation, selection, and reproduction. Two versions of the proposed methods have been presented here. The first one works on image pixels, while the second one tries on image derivative. The experiments were done on three different data sets that are used in literature and results were satisfactory. The results showed that the proposed method is much improved when compared to other related methods in most of the time especially in the case of real world images.

  20. Airborne remote sensing of water constituents at Lake Constance; Flugzeuggestuetzte Fernerkundung von Wasserinhaltsstoffen im Bodensee

    Energy Technology Data Exchange (ETDEWEB)

    Heege, T.

    2000-12-01

    An inversion scheme for the retrieval of water constituents in case II waters from airborne multispectral scanner data is presented. This method includes modules for the calculation of aerosol types and contents, for the correction of sun glitter radiances and for the atmospheric correction of the image data. In 1996 extensive measurements were performed to determine the optical properties in Lake Constance. In combination with data collected through many years within a project of the German Research Foundation (SFB 248), for the first time a data set of inherent optical parameters being specific for typical substances in the Lake could be established. By means of the inversions scheme and the specific optical properties, geo-coded maps of suspended matter and chlorophyll were calculated from the multispectral airborne measurements above Lake Constance. (orig.) [German] Zur Berechnung von Wasserinhaltsstoffen aus Daten flugzeuggetragener Multispektralscanner wird ein Inversionsverfahren vorgestellt. Es beinhaltet die Bestimmung von Aerosoltypen und -konzentrationen, die bildpunktweise Korrektur von Oberflaechenreflexionen des Sonnenlichtes und die Atmosphaerenkorrektur von Fernerkundungsdaten. Zur Erfassung der optischen Groessen im Wasser wurden umfangreiche Messkampagnen am Bodensee durchgefuehrt. Zusammen mit vieljaehrigen Datensaetzen des DFG-Sonderforschungsbereichs 248 wird damit erstmalig ein vollstaendiger Satz der inhaerenten optischen stoffspezifischen Groessen fuer den Bodensee bestimmt. Zur Validation werden diese anhand von verschiedenen Modellen zur Verknuepfung der inhaerenten Streu- und Absorptionskoeffizienten mit den messbaren Groessen Extinktion und diffuse Reflexion auf Konsistenz geprueft. Aus Befliegungen mit dem Multispektralscanner Daedalus werden mit den vorgestellten Verfahren und optischen Groessen georeferenzierte Verteilungskarten von Schwebstoff und Phytoplankton-Pigmenten berechnet. (orig.)

  1. Modelling colour constancy in fish: implications for vision and signalling in water.

    Science.gov (United States)

    Wilkins, Lucas; Marshall, N Justin; Johnsen, Sönke; Osorio, D

    2016-06-15

    Colour vision and colour signals are important to aquatic animals, but light scattering and absorption by water distorts spectral stimuli. To investigate the performance of colour vision in water, and to suggest how photoreceptor spectral sensitivities and body colours might evolve for visual communication, we model the effects of changes in viewing distance and depth on the appearance of fish colours for three teleosts: a barracuda, Sphyraena helleri, which is dichromatic and two damselfishes, Chromis verater and Chromis hanui, which are trichromatic. We assume that photoreceptors light-adapt to the background, thereby implementing the von Kries transformation, which can largely account for observed colour constancy in humans and other animals, including fish. This transformation does not, however, compensate for light scattering over variable viewing distances, which in less than a metre seriously impairs dichromatic colour vision, and makes judgement of colour saturation unreliable for trichromats. The von Kries transformation does substantially offset colour shifts caused by changing depth, so that from depths of 0 to 30 m modelled colour changes (i.e. failures of colour constancy) are sometimes negligible. However, the magnitudes and directions of remaining changes are complex, depending upon the specific spectral sensitivities of the receptors and the reflectance spectra. This predicts that when judgement of colour is important, the spectra of signalling colours and photoreceptor spectral sensitivities should be evolutionarily linked, with the colours dependent on photoreceptor spectral sensitivities, and vice versa. PMID:27045090

  2. Disparity-defined objects moving in depth do not elicit three-dimensional shape constancy.

    Science.gov (United States)

    Scarfe, P; Hibbard, P B

    2006-05-01

    Observers generally fail to recover three-dimensional shape accurately from binocular disparity. Typically, depth is overestimated at near distances and underestimated at far distances [Johnston, E. B. (1991). Systematic distortions of shape from stereopsis. Vision Research, 31, 1351-1360]. A simple prediction from this is that disparity-defined objects should appear to expand in depth when moving towards the observer, and compress in depth when moving away. However, additional information is provided when an object moves from which 3D Euclidean shape can be recovered, be this through the addition of structure from motion information [Richards, W. (1985). Structure from stereo and motion. Journal of the Optical Society of America A, 2, 343-349], or the use of non-generic strategies [Todd, J. T., & Norman, J. F. (2003). The visual perception of 3-D shape from multiple cues: Are observers capable of perceiving metric structure? Perception and Psychophysics, 65, 31-47]. Here, we investigated shape constancy for objects moving in depth. We found that to be perceived as constant in shape, objects needed to contract in depth when moving toward the observer, and expand in depth when moving away, countering the effects of incorrect distance scaling (Johnston, 1991). This is a striking example of the failure of shape constancy, but one that is predicted if observers neither accurately estimate object distance in order to recover Euclidean shape, nor are able to base their responses on a simpler processing strategy.

  3. COLOR IMAGES

    Directory of Open Access Journals (Sweden)

    Dominique Lafon

    2011-05-01

    Full Text Available The goal of this article is to present specific capabilities and limitations of the use of color digital images in a characterization process. The whole process is investigated, from the acquisition of digital color images to the analysis of the information relevant to various applications in the field of material characterization. A digital color image can be considered as a matrix of pixels with values expressed in a vector-space (commonly 3 dimensional space whose specificity, compared to grey-scale images, is to ensure a coding and a representation of the output image (visualisation printing that fits the human visual reality. In a characterization process, it is interesting to regard color image attnbutes as a set of visual aspect measurements on a material surface. Color measurement systems (spectrocolorimeters, colorimeters and radiometers and cameras use the same type of light detectors: most of them use Charge Coupled Devices sensors. The difference between the two types of color data acquisition systems is that color measurement systems provide a global information of the observed surface (average aspect of the surface: the color texture is not taken into account. Thus, it seems interesting to use imaging systems as measuring instruments for the quantitative characterization of the color texture.

  4. Peripheral Auditory Mechanisms

    CERN Document Server

    Hall, J; Hubbard, A; Neely, S; Tubis, A

    1986-01-01

    How weIl can we model experimental observations of the peripheral auditory system'? What theoretical predictions can we make that might be tested'? It was with these questions in mind that we organized the 1985 Mechanics of Hearing Workshop, to bring together auditory researchers to compare models with experimental observations. Tbe workshop forum was inspired by the very successful 1983 Mechanics of Hearing Workshop in Delft [1]. Boston University was chosen as the site of our meeting because of the Boston area's role as a center for hearing research in this country. We made a special effort at this meeting to attract students from around the world, because without students this field will not progress. Financial support for the workshop was provided in part by grant BNS- 8412878 from the National Science Foundation. Modeling is a traditional strategy in science and plays an important role in the scientific method. Models are the bridge between theory and experiment. Tbey test the assumptions made in experim...

  5. Color changes in objects in natural scenes as a function of observation distance and weather conditions.

    Science.gov (United States)

    Romero, Javier; Luzón-González, Raúl; Nieves, Juan L; Hernández-Andrés, Javier

    2011-10-01

    We have analyzed the changes in the color of objects in natural scenes due to atmospheric scattering according to changes in the distance of observation. Hook-shaped curves were found in the chromaticity diagram when the object moved from zero distance to long distances, where the object chromaticity coordinates approached the color coordinates of the horizon. This trend is the result of the combined effect of attenuation in the direct light arriving to the observer from the object and the airlight added during its trajectory. Atmospheric scattering leads to a fall in the object's visibility, which is measurable as a difference in color between the object and the background (taken here to be the horizon). Focusing on color difference instead of luminance difference could produce different visibility values depending on the color tolerance used. We assessed the cone-excitation ratio constancy for several objects at different distances. Affine relationships were obtained when an object's cone excitations were represented both at zero distance and increasing distances. These results could help to explain color constancy in natural scenes for objects at different distances, a phenomenon that has been pointed out by different authors. PMID:22016233

  6. Gender-related differences in physiologic color space: a functional transcranial Doppler (fTCD study

    Directory of Open Access Journals (Sweden)

    Njemanze Philip C

    2011-02-01

    Full Text Available Abstract Simultaneous color contrast and color constancy are memory processes associated with color vision, however, the gender-related differences of 'physiologic color space' remains unknown. Color processing was studied in 16 (8 men and 8 women right-handed healthy subjects using functional transcranial Doppler (fTCD technique. Mean flow velocity (MFV was recorded in both right (RMCA and left (LMCA middle cerebral arteries in dark and white light conditions, and during color (blue and yellow stimulations. The data was plotted in a 3D quadratic curve fit to derive a 'physiologic color space' showing the effects of luminance and chromatic contrasts. In men, wavelength-differencing of opponent pairs (yellow-blue was adjudged by changes in the RMCA MFV for Yellow plotted on the Y-axis, and the RMCA MFV for Blue plotted on the X-axis. In women, frequency-differencing for opponent pairs (blue-yellow was adjudged by changes in the LMCA MFV for Yellow plotted on the Y-axis, and the LMCA MFV for Blue plotted on the X-axis. The luminance effect on the LMCA MFV in response to white light with the highest luminous flux, was plotted on the (Z - axis, in both men and women. The 3D-color space for women was a mirror-image of that for men, and showed enhanced color constancy. The exponential function model was applied to the data in men, while the logarithmic function model was applied to the data in women. Color space determination may be useful in the study of color memory, adaptive neuroplasticity, cognitive impairment in stroke and neurodegenerative diseases.

  7. How metamer mismatching decreases as the number of colour mechanisms increases with implications for colour and lightness constancy.

    Science.gov (United States)

    Logvinenko, Alexander D; Funt, Brian; Godau, Christoph

    2015-08-01

    Metamer mismatching has been previously found to impose serious limitations on colour constancy. The extent of metamer mismatching is shown here to be considerably smaller for trichromats than for dichromats, and maximal for monochromats. The implications for achromatic colour perception are discussed. PMID:26054251

  8. Auditory short-term memory in the primate auditory cortex.

    Science.gov (United States)

    Scott, Brian H; Mishkin, Mortimer

    2016-06-01

    Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ׳working memory' bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive short-term memory (pSTM), is tractable to study in nonhuman primates, whose brain architecture and behavioral repertoire are comparable to our own. This review discusses recent advances in the behavioral and neurophysiological study of auditory memory with a focus on single-unit recordings from macaque monkeys performing delayed-match-to-sample (DMS) tasks. Monkeys appear to employ pSTM to solve these tasks, as evidenced by the impact of interfering stimuli on memory performance. In several regards, pSTM in monkeys resembles pitch memory in humans, and may engage similar neural mechanisms. Neural correlates of DMS performance have been observed throughout the auditory and prefrontal cortex, defining a network of areas supporting auditory STM with parallels to that supporting visual STM. These correlates include persistent neural firing, or a suppression of firing, during the delay period of the memory task, as well as suppression or (less commonly) enhancement of sensory responses when a sound is repeated as a ׳match' stimulus. Auditory STM is supported by a distributed temporo-frontal network in which sensitivity to stimulus history is an intrinsic feature of auditory processing. This article is part of a Special Issue entitled SI: Auditory working memory. PMID:26541581

  9. Auditory short-term memory in the primate auditory cortex.

    Science.gov (United States)

    Scott, Brian H; Mishkin, Mortimer

    2016-06-01

    Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ׳working memory' bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive short-term memory (pSTM), is tractable to study in nonhuman primates, whose brain architecture and behavioral repertoire are comparable to our own. This review discusses recent advances in the behavioral and neurophysiological study of auditory memory with a focus on single-unit recordings from macaque monkeys performing delayed-match-to-sample (DMS) tasks. Monkeys appear to employ pSTM to solve these tasks, as evidenced by the impact of interfering stimuli on memory performance. In several regards, pSTM in monkeys resembles pitch memory in humans, and may engage similar neural mechanisms. Neural correlates of DMS performance have been observed throughout the auditory and prefrontal cortex, defining a network of areas supporting auditory STM with parallels to that supporting visual STM. These correlates include persistent neural firing, or a suppression of firing, during the delay period of the memory task, as well as suppression or (less commonly) enhancement of sensory responses when a sound is repeated as a ׳match' stimulus. Auditory STM is supported by a distributed temporo-frontal network in which sensitivity to stimulus history is an intrinsic feature of auditory processing. This article is part of a Special Issue entitled SI: Auditory working memory.

  10. Tactile feedback improves auditory spatial localization

    OpenAIRE

    Gori, Monica; Vercillo, Tiziana; Sandini, Giulio; Burr, David

    2014-01-01

    Our recent studies suggest that congenitally blind adults have severely impaired thresholds in an auditory spatial bisection task, pointing to the importance of vision in constructing complex auditory spatial maps (Gori et al., 2014). To explore strategies that may improve the auditory spatial sense in visually impaired people, we investigated the impact of tactile feedback on spatial auditory localization in 48 blindfolded sighted subjects. We measured auditory spatial bisection thresholds b...

  11. Tactile feedback improves auditory spatial localization

    OpenAIRE

    Monica eGori; Tiziana eVercillo; Giulio eSandini; David eBurr

    2014-01-01

    Our recent studies suggest that congenitally blind adults have severely impaired thresholds in an auditory spatial-bisection task, pointing to the importance of vision in constructing complex auditory spatial maps (Gori et al., 2014). To explore strategies that may improve the auditory spatial sense in visually impaired people, we investigated the impact of tactile feedback on spatial auditory localization in 48 blindfolded sighted subjects. We measured auditory spatial bisection thresholds b...

  12. Auditory Neuropathy - A Case of Auditory Neuropathy after Hyperbilirubinemia

    Directory of Open Access Journals (Sweden)

    Maliheh Mazaher Yazdi

    2007-12-01

    Full Text Available Background and Aim: Auditory neuropathy is an hearing disorder in which peripheral hearing is normal, but the eighth nerve and brainstem are abnormal. By clinical definition, patient with this disorder have normal OAE, but exhibit an absent or severely abnormal ABR. Auditory neuropathy was first reported in the late 1970s as different methods could identify discrepancy between absent ABR and present hearing threshold. Speech understanding difficulties are worse than can be predicted from other tests of hearing function. Auditory neuropathy may also affect vestibular function. Case Report: This article presents electrophysiological and behavioral data from a case of auditory neuropathy in a child with normal hearing after bilirubinemia in a 5 years follow-up. Audiological findings demonstrate remarkable changes after multidisciplinary rehabilitation. Conclusion: auditory neuropathy may involve damage to the inner hair cells-specialized sensory cells in the inner ear that transmit information about sound through the nervous system to the brain. Other causes may include faulty connections between the inner hair cells and the nerve leading from the inner ear to the brain or damage to the nerve itself. People with auditory neuropathy have OAEs response but absent ABR and hearing loss threshold that can be permanent, get worse or get better.

  13. Auditory Processing Disorder in Children

    Science.gov (United States)

    ... free publications Find organizations Related Topics Auditory Neuropathy Autism Spectrum Disorder: Communication Problems in Children Dysphagia Quick ... NIH… Turning Discovery Into Health ® National Institute on Deafness and Other Communication Disorders 31 Center Drive, MSC ...

  14. Auditory Processing Disorder (For Parents)

    Science.gov (United States)

    ... and school. A positive, realistic attitude and healthy self-esteem in a child with APD can work wonders. And kids with APD can go on to ... Parents MORE ON THIS TOPIC Auditory Processing Disorder Special ...

  15. Verification of a novel method for tube voltage constancy measurement of orthovoltage x-ray irradiators

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chu; Belley, Matthew D. [Medical Physics Graduate Program, Duke University Medical Center, Durham, North Carolina 27705 and Duke Radiation Dosimetry Laboratory, Duke University Medical Center, Durham, North Carolina 27710 (United States); Chao, Nelson J. [Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710 and Department of Immunology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Dewhirst, Mark W. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Yoshizumi, Terry, E-mail: yoshi003@mc.duke.edu [Duke Radiation Dosimetry Laboratory, Duke University Medical Center, Durham, North Carolina 27710 (United States); Department of Radiology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States)

    2014-08-15

    Purpose: For orthovoltage x-ray irradiators, the tube voltage is one of the most fundamental system parameters as this directly relates to the dosimetry in radiation biology studies; however, to the best of our knowledge, there is no commercial portable quality assurance (QA) tool to directly test the constancy of the tube voltage greater than 160 kV. The purpose of this study is to establish the Beam Quality Index (BQI), a quantity strongly correlated to the tube voltage, as an alternative parameter for the verification of the tube voltage as part of the QA program of orthovoltage x-ray irradiators. Methods: A multipurpose QA meter and its associated data acquisition software were used to customize the measurement parameters to measure the BQI and collect its time-plot. BQI measurements were performed at 320 kV with four filtration levels on three orthovoltage x-ray irradiators of the same model, one of which had been recently energy-calibrated at the factory. Results: For each of the four filtration levels, the measured BQI values were in good agreement (<5%) between the three irradiators. BQI showed filtration-specificity, possibly due to the difference in beam quality. Conclusions: The BQI has been verified as a feasible alternative for monitoring the constancy of the tube voltage for orthovoltage irradiators. The time-plot of BQI offers information on the behavior of beam energy at different phases of the irradiation time line. In addition, this would provide power supply performance characteristics from initial ramp-up to plateau, and finally, the sharp drop-off at the end of the exposure.

  16. Hot electron plasma equilibrium and stability in the Constance B mirror experiment

    International Nuclear Information System (INIS)

    An experimental study of the equilibrium and macroscopic stability property of an electron cyclotron resonance heating (ECRH) generated plasma in a minimum-B mirror is presented. The Constance B mirror is a single cell quadrupole magnetic mirror in which high beta (β ≤ 0.3) hot electron plasmas (T/sub e/≅400 keV) are created with up to 4 kW of ECRH power. The plasma equilibrium profile is hollow and resembles the baseball seam geometry of the magnet which provides the confining magnetic field. This configuration coincides with the drift orbit of deeply trapped particles. The on-axis hollowness of the hot electron density profile is 50 /+-/ 10%, and the pressure profile is at least as hollow as, if not more than, the hot electron density profile. The hollow plasma equilibrium is macroscopically stable and generated in all the experimental conditions in which the machine has been operated. Small macroscopic plasma fluctuations in the range of the hot electron curvature drift frequency sometimes occur but their growth rate is small (ω/sub i//ω/sub r/ ≤ 10-2) and saturate at very low level (δB//bar B/ ≤ 10-3). Particle drift reversal is predicted to occur for the model pressure profile which best fits the experimental data under the typical operating conditions. No strong instability is observed when the plasma is near the drift reversal parameter regime, despite a theoretical prediction of instability under such conditions. The experiment shows that the cold electron population has no stabilizing effect to the hot electrons, which disagrees with current hot electron stability theories and results of previous maximum-B experiments. A theoretical analysis using MHD theory shows that the compressibility can stabilize a plasma with a hollowness of 20--30% in the Constance B mirror well. 57 refs

  17. Harmonious colors: from alchemy to science

    Science.gov (United States)

    Beretta, Giordano B.; Moroney, Nathan M.

    2012-01-01

    There is a very long tradition in designing color palettes for various applications, going back to at least the Upanishad. Although color palettes have been influenced by the available colorants, starting with the advent of aniline dyes in the late 1850s there have been few physical limits on the choice of individual colors. This abundance of choices exacerbates the problem of limiting the number of colors in a palette, i.e., in keeping them into a manageable quantity. For example, it is not practical for a car company to offer each model in hundreds of colors. Instead, for each model year a small number of color palettes is offered, each containing the colors for the body, trim, interior, etc. Another example is the fashion industry, where in addition to solid colors there are also patterns, leading to a huge variety of combinations that would be impossible to stock. The traditional solution is that of "color forecasting." Color consultants assess the sentiment or affective state of a target customer class and compare it with new colorants offered by the industry. They assemble a limited color palette, name the colors according to the sentiment, and publish their result. Textile manufacturers will produce fabrics in these colors and fashion designers will design clothes, accessories, and furniture based on these fabrics. Eventually, the media will communicate these forecasts to the consumers, who will be admired by their cohorts when they choose colors from the forecast palette, which by then is widely diffused. The color forecasting business is very labor intensive and difficult, thus for years computer engineers have tried to come up with algorithms to design harmonious color palettes, alas with little commercial success. For example, Johannes Itten's color theory has been implemented many times, but despite Itten's success in the Bauhaus artifacts, the computer tools have been of little utility. Indeed, contrary to the auditory sense, there is no known

  18. Color vision.

    Science.gov (United States)

    Gegenfurtner, Karl R; Kiper, Daniel C

    2003-01-01

    Color vision starts with the absorption of light in the retinal cone photoreceptors, which transduce electromagnetic energy into electrical voltages. These voltages are transformed into action potentials by a complicated network of cells in the retina. The information is sent to the visual cortex via the lateral geniculate nucleus (LGN) in three separate color-opponent channels that have been characterized psychophysically, physiologically, and computationally. The properties of cells in the retina and LGN account for a surprisingly large body of psychophysical literature. This suggests that several fundamental computations involved in color perception occur at early levels of processing. In the cortex, information from the three retino-geniculate channels is combined to enable perception of a large variety of different hues. Furthermore, recent evidence suggests that color analysis and coding cannot be separated from the analysis and coding of other visual attributes such as form and motion. Though there are some brain areas that are more sensitive to color than others, color vision emerges through the combined activity of neurons in many different areas.

  19. Hearing colors: an example of brain plasticity

    OpenAIRE

    Alfaro, Arantxa; Bernabeu, Ángela; Agulló, Carlos; Parra, Jaime; Fernández, Eduardo

    2015-01-01

    Sensory substitution devices (SSDs) are providing new ways for improving or replacing sensory abilities that have been lost due to disease or injury, and at the same time offer unprecedented opportunities to address how the nervous system could lead to an augmentation of its capacities. In this work we have evaluated a color-blind subject using a new visual-to-auditory SSD device called “Eyeborg”, that allows colors to be perceived as sounds. We used a combination of neuroimaging techniques i...

  20. Psychology of auditory perception.

    Science.gov (United States)

    Lotto, Andrew; Holt, Lori

    2011-09-01

    Audition is often treated as a 'secondary' sensory system behind vision in the study of cognitive science. In this review, we focus on three seemingly simple perceptual tasks to demonstrate the complexity of perceptual-cognitive processing involved in everyday audition. After providing a short overview of the characteristics of sound and their neural encoding, we present a description of the perceptual task of segregating multiple sound events that are mixed together in the signal reaching the ears. Then, we discuss the ability to localize the sound source in the environment. Finally, we provide some data and theory on how listeners categorize complex sounds, such as speech. In particular, we present research on how listeners weigh multiple acoustic cues in making a categorization decision. One conclusion of this review is that it is time for auditory cognitive science to be developed to match what has been done in vision in order for us to better understand how humans communicate with speech and music. WIREs Cogni Sci 2011 2 479-489 DOI: 10.1002/wcs.123 For further resources related to this article, please visit the WIREs website. PMID:26302301

  1. Modeling human color categorization: color discrimination and color memory

    NARCIS (Netherlands)

    Broek, van den E.L.; Hendriks, M.A.; Puts, M.J.H.; Vuurpijl, L.G.; Heskes, T.; Lucas, P.; Vuurpijl, L.G.; Wiegerinck, W.

    2003-01-01

    Color matching in Content-Based Image Retrieval is done using a color space and measuring distances between colors. Such an approach yields non-intuitive results for the user. We introduce color categories (or focal colors), determine that they are valid, and use them in two experiments. The experim

  2. Spatial imaging in color and HDR: prometheus unchained

    Science.gov (United States)

    McCann, John J.

    2013-03-01

    The Human Vision and Electronic Imaging Conferences (HVEI) at the IS and T/SPIE Electronic Imaging meetings have brought together research in the fundamentals of both vision and digital technology. This conference has incorporated many color disciplines that have contributed to the theory and practice of today's imaging: color constancy, models of vision, digital output, high-dynamic-range imaging, and the understanding of perceptual mechanisms. Before digital imaging, silver halide color was a pixel-based mechanism. Color films are closely tied to colorimetry, the science of matching pixels in a black surround. The quanta catch of the sensitized silver salts determines the amount of colored dyes in the final print. The rapid expansion of digital imaging over the past 25 years has eliminated the limitations of using small local regions in forming images. Spatial interactions can now generate images more like vision. Since the 1950's, neurophysiology has shown that post-receptor neural processing is based on spatial interactions. These results reinforced the findings of 19th century experimental psychology. This paper reviews the role of HVEI in color, emphasizing the interaction of research on vision and the new algorithms and processes made possible by electronic imaging.

  3. Neural Correlates of an Auditory Afterimage in Primary Auditory Cortex

    OpenAIRE

    Noreña, A. J.; Eggermont, J. J.

    2003-01-01

    The Zwicker tone (ZT) is defined as an auditory negative afterimage, perceived after the presentation of an appropriate inducer. Typically, a notched noise (NN) with a notch width of 1/2 octave induces a ZT with a pitch falling in the frequency range of the notch. The aim of the present study was to find potential neural correlates of the ZT in the primary auditory cortex of ketamine-anesthetized cats. Responses of multiunits were recorded simultaneously with two 8-electrode arrays during 1 s...

  4. Impossible promise: the child and the androgyne in Thomas Kilroy's The Secret Fall of Constance Wilde and My Scandalous Life

    Directory of Open Access Journals (Sweden)

    José Lanters

    2010-11-01

    Full Text Available In The Secret Fall of Constance Wilde and My Scandalous Life, the impossible ideals of perfect harmony between the sexes and perfect innocence are symbolically represented by the figures of the Androgyne and the child. In a process that illustrates the Wildean paradox that "each man kills the thing he loves," Oscar and Constance Wilde on the one hand, Alfred Douglas and Olive Custance on the other, fight each other over possession of their children, in that very act destroying both the ideal of androgynous harmony and that of childish innocence. Only by performing their worst nightmares, embracing the darkness within themselves, and acknowledging that innocence contains its own corruption, can the characters restore some form of equilibrium.

  5. Auditory-Verbal Comprehension Development of 2-5 Year Old Normal Persian Speaking Children in Tehran, Iran

    Directory of Open Access Journals (Sweden)

    Fariba Yadegari

    2011-06-01

    Full Text Available Background and Aim: Understanding and defining developmental norms of auditory comprehension is a necessity for detecting auditory-verbal comprehension impairments in children. We hereby investigated lexical auditory development of Persian (Farsi speaking children.Methods: In this cross-sectional study, auditory comprehension of four 2-5 year old normal children of adult’s child-directed utterance at available nurseries was observed by researchers primarily to gain a great number of comprehendible words for the children of the same age. The words were classified into nouns, verbs and adjectives. Auditory-verbal comprehension task items were also considered in 2 sections of subordinates and superordinates auditory comprehension. Colored pictures were provided for each item. Thirty 2-5 year old normal children were randomly selected from nurseries all over Tehran. Children were tested by this task and subsequently, mean of their correct response were analyzed. Results: The findings revealed that there is a high positive correlation between auditory-verbal comprehension and age (r=0.804, p=0.001. Comparing children in 3 age groups of 2-3, 3-4 and 4-5 year old, showed that subordinate and superordinate auditory comprehension of the former group is significantly lower (p0.05, while the difference between subordinate and superordinate auditory comprehension was significant in all age groups (p<0.05.Conclusion: Auditory-verbal comprehension develop much faster at lower than older ages and there is no prominent difference between word linguistic classes including nouns, verbs and adjectives. Slower development of superordinate auditory comprehension implies semantic hierarchical evolution of words.

  6. Retrospective analysis of linear accelerator output constancy checks using process control techniques.

    Science.gov (United States)

    Sanghangthum, Taweap; Suriyapee, Sivalee; Srisatit, Somyot; Pawlicki, Todd

    2013-01-01

    Shewhart control charts have previously been suggested as a process control tool for use in routine linear accelerator (linac) output verifications. However, a comprehensive approach to process control has not been investigated for linac output verifications. The purpose of this work is to investigate a comprehensive process control approach to linac output constancy quality assurance (QA). The RBA-3 dose constancy check was used to verify outputs of photon beams and electron beams delivered by a Varian Clinac 21EX linac. The data were collected during 2009 to 2010. Shewhart-type control charts, exponentially weighted moving average (EWMA) charts, and capability indices were applied to these processes. The Shewhart-type individuals chart (X-chart) was used and the number of data points used to calculate the control limits was varied. The parameters tested for the EWMA charts (smoothing parameter (λ) and the control limit width (L)) were λ = 0.05, L = 2.492; λ = 0.10, L = 2.703; and λ = 0.20, L = 2.860, as well as the number of points used to estimate the initial process mean and variation. Lastly, the number of in-control data points used to determine process capability (C(p)) and acceptability (C(pk)) were investigated, comparing the first in-control run to the longest in-control run of the process data. C(p) and C(pk) values greater than 1.0 were considered acceptable. The 95% confidence intervals were reported. The X-charts detected systematic errors (e.g., device setup errors). In-control run lengths on the X-charts varied from 5 to 30 output measurements (about one to seven months). EWMA charts showed in-control runs ranging from 9 to 33 output measurements (about two to eight months). The C(p) and C(pk) ratios are higher than 1.0 for all energies, except 12 and 20 MeV. However, 10 MV and 6, 9, and 16 MeV were in question when considering the 95% confidence limits. The X-chart should be calculated using 8-12 data points. For EWMA chart, using 4 data points

  7. Auditory Hallucinations in Acute Stroke

    Directory of Open Access Journals (Sweden)

    Yair Lampl

    2005-01-01

    Full Text Available Auditory hallucinations are uncommon phenomena which can be directly caused by acute stroke, mostly described after lesions of the brain stem, very rarely reported after cortical strokes. The purpose of this study is to determine the frequency of this phenomenon. In a cross sectional study, 641 stroke patients were followed in the period between 1996–2000. Each patient underwent comprehensive investigation and follow-up. Four patients were found to have post cortical stroke auditory hallucinations. All of them occurred after an ischemic lesion of the right temporal lobe. After no more than four months, all patients were symptom-free and without therapy. The fact the auditory hallucinations may be of cortical origin must be taken into consideration in the treatment of stroke patients. The phenomenon may be completely reversible after a couple of months.

  8. Colored Preons

    CERN Document Server

    Finkelstein, Robert J

    2009-01-01

    Previous studies have suggested complementary models of the elementary particles as (a) quantum knots and (b) preonic nuclei that are field and particle descriptions, respectively, of the same particles. This earlier work, carried out in the context of standard electroweak (SU(2) x U(1)) physics, is here extended to the strong interactions by the introduction of color (SU(3)) charges.

  9. Color tejido

    OpenAIRE

    Rius Tormo, Palmira

    2010-01-01

    La exposición que se propone tiene como núcleo principal el color y muestra las posibilidades expresivas que aporta a los diferentes materiales. Las 7 obras presentadas buscan la armonía estética y la fuerza simbólica.

  10. Comparison of Aerobic Methanotrophic Communities in Littoral and Profundal Sediments of Lake Constance by a Molecular Approach▿

    OpenAIRE

    Rahalkar, Monali; Schink, Bernhard

    2007-01-01

    Analysis of pmoA and 16S rRNA gene clone libraries of methanotrophic bacteria in Lake Constance revealed an overall dominance of type I methanotrophs in both littoral and profundal sediments. The sediments exhibited minor differences in their methanotrophic community structures. Type X methanotrophs made up a significant part of the clone libraries only in the profundal sediment and were also found only there as a prominent peak by T-RFLP analyses.

  11. Adaptation in the auditory system: an overview

    OpenAIRE

    David ePérez-González; Malmierca, Manuel S.

    2014-01-01

    The early stages of the auditory system need to preserve the timing information of sounds in order to extract the basic features of acoustic stimuli. At the same time, different processes of neuronal adaptation occur at several levels to further process the auditory information. For instance, auditory nerve fiber responses already experience adaptation of their firing rates, a type of response that can be found in many other auditory nuclei and may be useful for emphasizing the onset of the s...

  12. Educational Testing of an Auditory Display of Mars Gamma Ray Spectrometer Data

    Science.gov (United States)

    Keller, J. M.; Pompea, S. M.; Prather, E. E.; Slater, T. F.; Boynton, W. V.; Enos, H. L.; Quinn, M.

    2003-12-01

    A unique, alternative educational and public outreach product was created to investigate the use and effectiveness of auditory displays in science education. The product, which allows students to both visualize and hear seasonal variations in data detected by the Gamma Ray Spectrometer (GRS) aboard the Mars Odyssey spacecraft, consists of an animation of false-color maps of hydrogen concentrations on Mars along with a musical presentation, or sonification, of the same data. Learners can access this data using the visual false-color animation, the auditory false-pitch sonification, or both. Central to the development of this product is the question of its educational effectiveness and implementation. During the spring 2003 semester, three sections of an introductory astronomy course, each with ˜100 non-science undergraduates, were presented with one of three different exposures to GRS hydrogen data: one auditory, one visual, and one both auditory and visual. Student achievement data was collected through use of multiple-choice and open-ended surveys administered before, immediately following, and three and six weeks following the experiment. It was found that the three student groups performed equally well in their ability to perceive and interpret the data presented. Additionally, student groups exposed to the auditory display reported a higher interest and engagement level than the student group exposed to the visual data alone. Based upon this preliminary testing,we have made improvements to both the educational product and our evaluation protocol. This fall, we will conduct further testing with ˜100 additional students, half receiving auditory data and half receiving visual data, and we will conduct interviews with individual students as they interface with the auditory display. Through this process, we hope to further assess both learning and engagement gains associated with alternative and multi-modal representations of scientific data that extend beyond

  13. Formation of brominated trihalomethanes in chlorinated drinking-water from Lake Constance

    International Nuclear Information System (INIS)

    The formation of trihalomethanes (THMs) in raw water and drinking water from Lake Constance containing low amounts of DOC and bromide was studied with special emphasis on brominated trihalomethanes (Br-THMs). If the raw water was ozonated prior to chlorination, the formation of THMs was reduced by 37%, and if a rapid sandfiltration was interposed, the THM-formation was again slightly enhanced. The percentage of Br-THMs on total-THMs increased from 16% to 35% during the treatment process. In the drinking water distribution system of BWV the formation of Br-THMs and CHCl3 was studied with respect to residence time and post-chlorination. Unless the post-chlorination was performed, the THM-formation in the distribution system resembled that obtained from laboratory studies, except for small amounts of THMs being purged due to transport in the mains and residence in the reservoirs. Post-chlorination increased CHCl3- and the CHBrCl2-formation, but there was no effect on the formation of CHBr2Cl and CHBr3. However, the total THM-concentration in the drinking water never exceeded the German drinking water standard of 10 μg/L. (orig.)

  14. The conceptualization of time and the constancy of the speed of light

    CERN Document Server

    Guerra, V; Guerra, Vasco; Abreu, Rodrigo de

    2005-01-01

    In this work we show that the null result of the Michelson-Morley experiment in vacuum is deeply connected with the notion of time. It can be deduced without any mathematics only from the assumption that all good clocks can be used to measure time with the same results, independently of the machinery involved in their manufacturing. A second important assumption, intrinsic to the very notion of time, is that clocks measure time in the same way in different frames, i.e., the notion of time is the same in all inertial frames. Under this assumption, we point out that the "postulate" of constancy of the "two-way" speed of light in vacuum in all frames independently of the state of motion of the emitting body is also strongly related to the concept of time, together with the existence of a limit speed in the "rest frame". This postulate simply results from the construction of clocks where tic-tacs are made by objects traveling with the limit speed.

  15. On the Basis of Synaptic Integration Constancy during Growth of a Neuronal Circuit

    Science.gov (United States)

    De-La-Rosa Tovar, Adriana; Mishra, Prashant K.; De-Miguel, Francisco F.

    2016-01-01

    We studied how a neuronal circuit composed of two neuron types connected by chemical and electrical synapses maintains constant its integrative capacities as neurons grow. For this we combined electrophysiological experiments with mathematical modeling in pairs of electrically-coupled Retzius neurons from postnatal to adult leeches. The electrically-coupled dendrites of both Retzius neurons receive a common chemical input, which produces excitatory postsynaptic potentials (EPSPs) with varying amplitudes. Each EPSP spreads to the soma, but also crosses the electrical synapse to arrive at the soma of the coupled neuron. The leak of synaptic current across the electrical synapse reduces the amplitude of the EPSPs in proportion to the coupling ratio. In addition, summation of EPSPs generated in both neurons generates the baseline action potentials of these serotonergic neurons. To study how integration is adjusted as neurons grow, we first studied the characteristics of the chemical and electrical connections onto the coupled dendrites of neuron pairs with soma diameters ranging from 21 to 75 μm. Then by feeding a mathematical model with the neuronal voltage responses to pseudorandom noise currents we obtained the values of the coupling ratio, the membrane resistance of the soma (rm) and dendrites (rdend), the space constant (λ) and the characteristic dendritic length (L = l/λ). We found that the EPSPs recorded from the somata were similar regardless on the neuron size. However, the amplitude of the EPSPs and the firing frequency of the neurons were inversely proportional to the coupling ratio of the neuron pair, which also was independent from the neuronal size. This data indicated that the integrative constancy relied on the passive membrane properties. We show that the growth of Retzius neurons was compensated by increasing the membrane resistance of the dendrites and therefore the λ value. By solely increasing the dendrite resistance this circuit maintains

  16. ON THE BASIS OF SYNAPTIC INTEGRATION CONSTANCY DURING GROWTH OF A NEURONAL CIRCUIT

    Directory of Open Access Journals (Sweden)

    Adriana De la Rosa

    2016-08-01

    Full Text Available We studied how a neuronal circuit composed of two neuron types connected by chemical and electrical synapses maintains constant its integrative capacities as neurons grow. For this we combined electrophysiological experiments with mathematical modeling in pairs of electrically-coupled Retzius neurons from postnatal to adult leeches. The electrically-coupled dendrites of both Retzius neurons receive a common chemical input, which produces EPSPs with varying amplitudes. Each EPSP spreads to the soma, but also crosses the electrical synapse to arrive at the soma of the coupled neuron. The leak of synaptic current across the electrical synapse reduces the amplitude of the EPSPs in proportion to the coupling ratio. In addition, summation of EPSPs generated in both neurons generates the baseline action potentials of these serotonergic neurons. To study how integration is adjusted as neurons grow we first studied the characteristics of the chemical and electrical connections onto the coupled dendrites of neuron pairs with soma diameters ranging from 21 to 75 µm. Then by feeding a mathematical model with the neuronal voltage responses to pseudorandom noise currents we obtained the values of the coupling ratio, the membrane resistance of the soma (rm and dendrites (rdend, the space constant (λ and the characteristic dendritic length (L=l/λ . We found that the EPSPs recorded from the somata were similar regardless on the neuron size. However, the amplitude of the EPSPs and the firing frequency of the neurons were inversely proportional to the coupling ratio of the neuron pair, which also was independent form the neuronal size. This data indicated that the integrative constancy relied on the passive membrane properties. We show that the growth of Retzius neurons was compensated by increasing the membrane resistance of the dendrites and therefore the λ value. By solely increasing the dendrite resistance this circuit maintains constant its integrative

  17. On the Basis of Synaptic Integration Constancy during Growth of a Neuronal Circuit.

    Science.gov (United States)

    De-La-Rosa Tovar, Adriana; Mishra, Prashant K; De-Miguel, Francisco F

    2016-01-01

    We studied how a neuronal circuit composed of two neuron types connected by chemical and electrical synapses maintains constant its integrative capacities as neurons grow. For this we combined electrophysiological experiments with mathematical modeling in pairs of electrically-coupled Retzius neurons from postnatal to adult leeches. The electrically-coupled dendrites of both Retzius neurons receive a common chemical input, which produces excitatory postsynaptic potentials (EPSPs) with varying amplitudes. Each EPSP spreads to the soma, but also crosses the electrical synapse to arrive at the soma of the coupled neuron. The leak of synaptic current across the electrical synapse reduces the amplitude of the EPSPs in proportion to the coupling ratio. In addition, summation of EPSPs generated in both neurons generates the baseline action potentials of these serotonergic neurons. To study how integration is adjusted as neurons grow, we first studied the characteristics of the chemical and electrical connections onto the coupled dendrites of neuron pairs with soma diameters ranging from 21 to 75 μm. Then by feeding a mathematical model with the neuronal voltage responses to pseudorandom noise currents we obtained the values of the coupling ratio, the membrane resistance of the soma (rm ) and dendrites (r dend), the space constant (λ) and the characteristic dendritic length (L = l/λ). We found that the EPSPs recorded from the somata were similar regardless on the neuron size. However, the amplitude of the EPSPs and the firing frequency of the neurons were inversely proportional to the coupling ratio of the neuron pair, which also was independent from the neuronal size. This data indicated that the integrative constancy relied on the passive membrane properties. We show that the growth of Retzius neurons was compensated by increasing the membrane resistance of the dendrites and therefore the λ value. By solely increasing the dendrite resistance this circuit maintains

  18. Perception-memory interactions reveal a computational strategy for perceptual constancy.

    Science.gov (United States)

    Olkkonen, Maria; Saarela, Toni P; Allred, Sarah R

    2016-01-01

    A key challenge for the visual system is to extract constant object properties from incoming sensory information. This information is ambiguous because the same sensory signal can arise from many combinations of object properties and viewing conditions and noisy because of the variability in sensory encoding. The competing accounts for perceptual constancy of surface lightness fall into two classes of model: One derives lightness estimates from border contrasts, and another explicitly infers surface reflectance. To test these accounts, we combined a novel psychophysical task with probabilistic implementations of both models. Observers compared the lightness of two stimuli under a memory demand (a delay between the stimuli), a context change (different surround luminance), or both. Memory biased perceived lightness toward the mean of the whole stimulus ensemble. Context change caused the classical simultaneous lightness contrast effect, in which a target appears lighter against a dark surround and darker against a light surround. These effects were not independent: Combined memory load and context change elicited a bias smaller than predicted assuming an independent combination of biases. Both models explain the memory bias as an effect of prior expectations on perception. Both models also produce a context effect, but only the reflectance model correctly describes the magnitude. The reflectance model, finally, captures the memory-context interaction better than the contrast model, both qualitatively and quantitatively. We conclude that (a) lightness perception is more consistent with reflectance inference than contrast coding and (b) adding a memory demand to a perceptual task both renders it more ecologically valid and helps adjudicate between competing models.

  19. Spatially explicit exposure assessment for small streams in catchments of the orchard growing region `Lake Constance

    Science.gov (United States)

    Golla, B.; Bach, M.; Krumpe, J.

    2009-04-01

    1. Introduction Small streams differ greatly from the standardised water body used in the context of aquatic risk assessment for the regulation of plant protection products in Germany. The standard water body is static, with a depth of 0.3 m and a width of 1.0 m. No dilution or water replacement takes place. Spray drift happens always in direction to the water body. There is no variability in drift deposition rate (90th percentile spray drift deposition values [2]). There is no spray drift filtering by vegetation. The application takes place directly adjacent to the water body. In order to establish a more realistic risk assessment procedure the Federal Office for Consumer Protection and Food Safety (BVL) and the Federal Environment Agency (UBA) aggreed to replace deterministic assumptions with data distributions and spatially explicit data and introduce probabilistic methods [3, 4, 5]. To consider the spatial and temporal variability in the exposure situations of small streams the hydraulic and morphological characteristics of catchments need to be described as well as the spatial distribution of fields treated with pesticides. As small streams are the dominant type of water body in most German orchard regions, we use the growing region Lake Constance as pilot region. 2. Materials and methods During field surveys we derive basic morphological parameters for small streams in the Lake Constance region. The mean water width/depth ratio is 13 with a mean depth of 0.12 m. The average residence time is 5.6 s/m (n=87) [1]. Orchards are mostly located in the upper parts of the catchments. Based on an authoritative dataset on rivers and streams of Germany (ATKIS DLM25) we constructed a directed network topology for the Lake Constance region. The gradient of the riverbed is calculated for river stretches of > 500 m length. The network for the pilot region consists of 2000 km rivers and streams. 500 km stream length are located within a distance of 150 m to orchards. Within

  20. Color improves "visual" acuity via sound.

    Science.gov (United States)

    Levy-Tzedek, Shelly; Riemer, Dar; Amedi, Amir

    2014-01-01

    Visual-to-auditory sensory substitution devices (SSDs) convey visual information via sound, with the primary goal of making visual information accessible to blind and visually impaired individuals. We developed the EyeMusic SSD, which transforms shape, location, and color information into musical notes. We tested the "visual" acuity of 23 individuals (13 blind and 10 blindfolded sighted) on the Snellen tumbling-E test, with the EyeMusic. Participants were asked to determine the orientation of the letter "E." The test was repeated twice: in one test, the letter "E" was drawn with a single color (white), and in the other test, with two colors (red and white). In the latter case, the vertical line in the letter, when upright, was drawn in red, with the three horizontal lines drawn in white. We found no significant differences in performance between the blind and the sighted groups. We found a significant effect of the added color on the "visual" acuity. The highest acuity participants reached in the monochromatic test was 20/800, whereas with the added color, acuity doubled to 20/400. We conclude that color improves "visual" acuity via sound. PMID:25426015

  1. Conceptual priming for realistic auditory scenes and for auditory words.

    Science.gov (United States)

    Frey, Aline; Aramaki, Mitsuko; Besson, Mireille

    2014-02-01

    Two experiments were conducted using both behavioral and Event-Related brain Potentials methods to examine conceptual priming effects for realistic auditory scenes and for auditory words. Prime and target sounds were presented in four stimulus combinations: Sound-Sound, Word-Sound, Sound-Word and Word-Word. Within each combination, targets were conceptually related to the prime, unrelated or ambiguous. In Experiment 1, participants were asked to judge whether the primes and targets fit together (explicit task) and in Experiment 2 they had to decide whether the target was typical or ambiguous (implicit task). In both experiments and in the four stimulus combinations, reaction times and/or error rates were longer/higher and the N400 component was larger to ambiguous targets than to conceptually related targets, thereby pointing to a common conceptual system for processing auditory scenes and linguistic stimuli in both explicit and implicit tasks. However, fine-grained analyses also revealed some differences between experiments and conditions in scalp topography and duration of the priming effects possibly reflecting differences in the integration of perceptual and cognitive attributes of linguistic and nonlinguistic sounds. These results have clear implications for the building-up of virtual environments that need to convey meaning without words. PMID:24378910

  2. Psychophysiological responses to auditory change.

    Science.gov (United States)

    Chuen, Lorraine; Sears, David; McAdams, Stephen

    2016-06-01

    A comprehensive characterization of autonomic and somatic responding within the auditory domain is currently lacking. We studied whether simple types of auditory change that occur frequently during music listening could elicit measurable changes in heart rate, skin conductance, respiration rate, and facial motor activity. Participants heard a rhythmically isochronous sequence consisting of a repeated standard tone, followed by a repeated target tone that changed in pitch, timbre, duration, intensity, or tempo, or that deviated momentarily from rhythmic isochrony. Changes in all parameters produced increases in heart rate. Skin conductance response magnitude was affected by changes in timbre, intensity, and tempo. Respiratory rate was sensitive to deviations from isochrony. Our findings suggest that music researchers interpreting physiological responses as emotional indices should consider acoustic factors that may influence physiology in the absence of induced emotions. PMID:26927928

  3. Reality of auditory verbal hallucinations

    Science.gov (United States)

    Valkonen-Korhonen, Minna; Holi, Matti; Therman, Sebastian; Lehtonen, Johannes; Hari, Riitta

    2009-01-01

    Distortion of the sense of reality, actualized in delusions and hallucinations, is the key feature of psychosis but the underlying neuronal correlates remain largely unknown. We studied 11 highly functioning subjects with schizophrenia or schizoaffective disorder while they rated the reality of auditory verbal hallucinations (AVH) during functional magnetic resonance imaging (fMRI). The subjective reality of AVH correlated strongly and specifically with the hallucination-related activation strength of the inferior frontal gyri (IFG), including the Broca's language region. Furthermore, how real the hallucination that subjects experienced was depended on the hallucination-related coupling between the IFG, the ventral striatum, the auditory cortex, the right posterior temporal lobe, and the cingulate cortex. Our findings suggest that the subjective reality of AVH is related to motor mechanisms of speech comprehension, with contributions from sensory and salience-detection-related brain regions as well as circuitries related to self-monitoring and the experience of agency. PMID:19620178

  4. Auditory distraction and serial memory

    OpenAIRE

    Jones, D M; Hughes, Rob; Macken, W.J.

    2010-01-01

    One mental activity that is very vulnerable to auditory distraction is serial recall. This review of the contemporary findings relating to serial recall charts the key determinants of distraction. It is evident that there is one form of distraction that is a joint product of the cognitive characteristics of the task and of the obligatory cognitive processing of the sound. For sequences of sound, distraction appears to be an ineluctable product of similarity-of-process, specifically, the seria...

  5. Reality of auditory verbal hallucinations

    OpenAIRE

    Raij TT; Valkonen-Korhonen M; Holi M; Therman S; Lehtonen J; Hari R

    2009-01-01

    Distortion of the sense of reality, actualized in delusions and hallucinations, is the key feature of psychosis but the underlying neuronal correlates remain largely unknown. We studied 11 highly functioning subjects with schizophrenia or schizoaffective disorder while they rated the reality of auditory verbal hallucinations (AVH) during functional magnetic resonance imaging (fMRI). The subjective reality of AVH correlated strongly and specifically with the hallucination-related activation st...

  6. The Disunity of Color

    OpenAIRE

    Matthen, Mohan

    1999-01-01

    What is color? What is color vision? Most philosophers answer by reference to humans: to human color qualia, or to the environmental properties or "quality spaces" perceived by humans. It is argued, with reference to empirical findings concerning comparative color vision and the evolution of color vision, that all such attempts are mistaken. An adequate definition of color vision must eschew reference to its outputs in the human cognition and refer only to inputs: color vision consists in...

  7. Zooplankton communities in a large prealpine lake, Lake Constance: comparison between the Upper and the Lower Lake

    OpenAIRE

    Gerhard MAIER; Pfeiffer, Martin; Hans Bernd STICH

    2005-01-01

    The zooplankton communities of two basins of a large lake, Lake Constance, were compared during the years 2002 and 2003. The two basins differ in morphology, physical and chemical conditions. The Upper Lake basin has a surface area of 470 km2, a mean depth of 100 and a maximum depth of 250 m; the Lower Lake basin has a surface area of 62 km2, a mean depth of only 13 and a maximum depth of 40 m. Nutrient, chlorophyll-a concentrations and mean temperatures are somewhat higher in the Lower than ...

  8. Nature and origin of the hydrocarbons in sediments of Lake Constance. Art und Herkunft der Kohlenwasserstoffe in Sedimenten des Bodensees

    Energy Technology Data Exchange (ETDEWEB)

    Giger, W.; Schaffner, C.; Hollerbach, A.; Kalbfus, W.; Wachs, B.; Wagner, H.; Mueller, G.; Mueller, H.

    1982-04-01

    Six samples of sediment were taken from Lake Constance and hydrocarbons tested for biogenic or mineral oil origin with the following results: The high proportion of polar extractable matter is indicative of a biogenic origin. 2. The alkanes and alkenes are largely of biogenic composition, whereby an indication of fossile hydrocarbons was found for two samples. A distribution could not be made between mineral oil-derived hydrocarbons and other fossile hydrocarbons because of the low proportions present. 3. The composition of the aromatic fraction was indicative of a biogenic or pyrolytic origin.

  9. Auditory sequence analysis and phonological skill.

    Science.gov (United States)

    Grube, Manon; Kumar, Sukhbinder; Cooper, Freya E; Turton, Stuart; Griffiths, Timothy D

    2012-11-01

    This work tests the relationship between auditory and phonological skill in a non-selected cohort of 238 school students (age 11) with the specific hypothesis that sound-sequence analysis would be more relevant to phonological skill than the analysis of basic, single sounds. Auditory processing was assessed across the domains of pitch, time and timbre; a combination of six standard tests of literacy and language ability was used to assess phonological skill. A significant correlation between general auditory and phonological skill was demonstrated, plus a significant, specific correlation between measures of phonological skill and the auditory analysis of short sequences in pitch and time. The data support a limited but significant link between auditory and phonological ability with a specific role for sound-sequence analysis, and provide a possible new focus for auditory training strategies to aid language development in early adolescence. PMID:22951739

  10. Speech distortion measure based on auditory properties

    Institute of Scientific and Technical Information of China (English)

    CHEN Guo; HU Xiulin; ZHANG Yunyu; ZHU Yaoting

    2000-01-01

    The Perceptual Spectrum Distortion (PSD), based on auditory properties of human being, is presented to measure speech distortion. The PSD measure calculates the speech distortion distance by simulating the auditory properties of human being and converting short-time speech power spectrum to auditory perceptual spectrum. Preliminary simulative experiments in comparison with the Itakura measure have been done. The results show that the PSD measure is a perferable speech distortion measure and more consistent with subjective assessment of speech quality.

  11. Auditory stimulation and cardiac autonomic regulation

    OpenAIRE

    Vitor E Valenti; Guida, Heraldo L.; Frizzo, Ana C F; Cardoso, Ana C. V.; Vanderlei, Luiz Carlos M; Luiz Carlos de Abreu

    2012-01-01

    Previous studies have already demonstrated that auditory stimulation with music influences the cardiovascular system. In this study, we described the relationship between musical auditory stimulation and heart rate variability. Searches were performed with the Medline, SciELO, Lilacs and Cochrane databases using the following keywords: "auditory stimulation", "autonomic nervous system", "music" and "heart rate variability". The selected studies indicated that there is a strong correlation bet...

  12. Mechanisms of Auditory Verbal Hallucination in Schizophrenia

    OpenAIRE

    Raymond eCho; Wayne eWu

    2013-01-01

    Recent work on the mechanisms underlying auditory verbal hallucination (AVH) has been heavily informed by self-monitoring accounts that postulate defects in an internal monitoring mechanism as the basis of AVH. A more neglected alternative is an account focusing on defects in auditory processing, namely a spontaneous activation account of auditory activity underlying AVH. Science is often aided by putting theories in competition. Accordingly, a discussion that systematically contrasts the two...

  13. a New Color Correction Method for Underwater Imaging

    Science.gov (United States)

    Bianco, G.; Muzzupappa, M.; Bruno, F.; Garcia, R.; Neumann, L.

    2015-04-01

    Recovering correct or at least realistic colors of underwater scenes is a very challenging issue for imaging techniques, since illumination conditions in a refractive and turbid medium as the sea are seriously altered. The need to correct colors of underwater images or videos is an important task required in all image-based applications like 3D imaging, navigation, documentation, etc. Many imaging enhancement methods have been proposed in literature for these purposes. The advantage of these methods is that they do not require the knowledge of the medium physical parameters while some image adjustments can be performed manually (as histogram stretching) or automatically by algorithms based on some criteria as suggested from computational color constancy methods. One of the most popular criterion is based on gray-world hypothesis, which assumes that the average of the captured image should be gray. An interesting application of this assumption is performed in the Ruderman opponent color space lαβ, used in a previous work for hue correction of images captured under colored light sources, which allows to separate the luminance component of the scene from its chromatic components. In this work, we present the first proposal for color correction of underwater images by using lαβ color space. In particular, the chromatic components are changed moving their distributions around the white point (white balancing) and histogram cutoff and stretching of the luminance component is performed to improve image contrast. The experimental results demonstrate the effectiveness of this method under gray-world assumption and supposing uniform illumination of the scene. Moreover, due to its low computational cost it is suitable for real-time implementation.

  14. Using color management in color document processing

    Science.gov (United States)

    Nehab, Smadar

    1995-04-01

    Color Management Systems have been used for several years in Desktop Publishing (DTP) environments. While this development hasn't matured yet, we are already experiencing the next generation of the color imaging revolution-Device Independent Color for the small office/home office (SOHO) environment. Though there are still open technical issues with device independent color matching, they are not the focal point of this paper. This paper discusses two new and crucial aspects in using color management in color document processing: the management of color objects and their associated color rendering methods; a proposal for a precedence order and handshaking protocol among the various software components involved in color document processing. As color peripherals become affordable to the SOHO market, color management also becomes a prerequisite for common document authoring applications such as word processors. The first color management solutions were oriented towards DTP environments whose requirements were largely different. For example, DTP documents are image-centric, as opposed to SOHO documents that are text and charts centric. To achieve optimal reproduction on low-cost SOHO peripherals, it is critical that different color rendering methods are used for the different document object types. The first challenge in using color management of color document processing is the association of rendering methods with object types. As a result of an evolutionary process, color matching solutions are now available as application software, as driver embedded software and as operating system extensions. Consequently, document processing faces a new challenge, the correct selection of the color matching solution while avoiding duplicate color corrections.

  15. Auditory Training and Its Effects upon the Auditory Discrimination and Reading Readiness of Kindergarten Children.

    Science.gov (United States)

    Cullen, Minga Mustard

    The purpose of this investigation was to evaluate the effects of a systematic auditory training program on the auditory discrimination ability and reading readiness of 55 white, middle/upper middle class kindergarten students. Following pretesting with the "Wepman Auditory Discrimination Test,""The Clymer-Barrett Prereading Battery," and the…

  16. Effects of Methylphenidate (Ritalin) on Auditory Performance in Children with Attention and Auditory Processing Disorders.

    Science.gov (United States)

    Tillery, Kim L.; Katz, Jack; Keller, Warren D.

    2000-01-01

    A double-blind, placebo-controlled study examined effects of methylphenidate (Ritalin) on auditory processing in 32 children with both attention deficit hyperactivity disorder and central auditory processing (CAP) disorder. Analyses revealed that Ritalin did not have a significant effect on any of the central auditory processing measures, although…

  17. Central auditory function of deafness genes.

    Science.gov (United States)

    Willaredt, Marc A; Ebbers, Lena; Nothwang, Hans Gerd

    2014-06-01

    The highly variable benefit of hearing devices is a serious challenge in auditory rehabilitation. Various factors contribute to this phenomenon such as the diversity in ear defects, the different extent of auditory nerve hypoplasia, the age of intervention, and cognitive abilities. Recent analyses indicate that, in addition, central auditory functions of deafness genes have to be considered in this context. Since reduced neuronal activity acts as the common denominator in deafness, it is widely assumed that peripheral deafness influences development and function of the central auditory system in a stereotypical manner. However, functional characterization of transgenic mice with mutated deafness genes demonstrated gene-specific abnormalities in the central auditory system as well. A frequent function of deafness genes in the central auditory system is supported by a genome-wide expression study that revealed significant enrichment of these genes in the transcriptome of the auditory brainstem compared to the entire brain. Here, we will summarize current knowledge of the diverse central auditory functions of deafness genes. We furthermore propose the intimately interwoven gene regulatory networks governing development of the otic placode and the hindbrain as a mechanistic explanation for the widespread expression of these genes beyond the cochlea. We conclude that better knowledge of central auditory dysfunction caused by genetic alterations in deafness genes is required. In combination with improved genetic diagnostics becoming currently available through novel sequencing technologies, this information will likely contribute to better outcome prediction of hearing devices.

  18. Visual discrimination of rotated 3D objects in Malawi cichlids (Pseudotropheus sp.): a first indication for form constancy in fishes.

    Science.gov (United States)

    Schluessel, V; Kraniotakes, H; Bleckmann, H

    2014-03-01

    Fish move in a three-dimensional environment in which it is important to discriminate between stimuli varying in colour, size, and shape. It is also advantageous to be able to recognize the same structures or individuals when presented from different angles, such as back to front or front to side. This study assessed visual discrimination abilities of rotated three-dimensional objects in eight individuals of Pseudotropheus sp. using various plastic animal models. All models were displayed in two choice experiments. After successful training, fish were presented in a range of transfer tests with objects rotated in the same plane and in space by 45° and 90° to the side or to the front. In one experiment, models were additionally rotated by 180°, i.e., shown back to front. Fish showed quick associative learning and with only one exception successfully solved and finished all experimental tasks. These results provide first evidence for form constancy in this species and in fish in general. Furthermore, Pseudotropheus seemed to be able to categorize stimuli; a range of turtle and frog models were recognized independently of colour and minor shape variations. Form constancy and categorization abilities may be important for behaviours such as foraging, recognition of predators, and conspecifics as well as for orienting within habitats or territories. PMID:23982620

  19. Transformation of the Visual Afterimage Under Subject's Eye and Body Movements and the Visual Field Constancy Mechanisms.

    Science.gov (United States)

    Zenkin, Gary M; Petrov, Alexander P

    2015-01-01

    Two types of positive afterimages differing in their structural complexity--called poor and rich--were used to investigate the visual field constancy mechanisms during eye and head movements. In the case of a poor afterimage, consistent with Emmert's law, every eye and head movement caused the afterimage to appear moving (in exactly the same way), unlike a real object, which appeared to remain stationary during those same eye and head movements (although its retinal image moved opposite to the eye movement). However, in the case of a rich afterimage, the afterimage appeared stationary during eye movements, while a small stationary test light in the real space appeared to move, violating Emmert's law. It is suggested that, in these two cases, the different apparent transformations reflected functioning of different constancy mechanisms. Both mechanisms implement projection of retinal images upon a hypothetical constant visual screen in strict accordance with the subject's movements but in two different ways. The experiments have indicated that, during binocular fusion, the visual afferent system is able to use information from the structural organization of the visual flow to implement the visual field stability and to calculate gaze direction independently of proprioceptive signals. PMID:26562912

  20. Optical angular constancy is maintained as a navigational control strategy when pursuing robots moving along complex pathways.

    Science.gov (United States)

    Wang, Wei; McBeath, Michael K; Sugar, Thomas G

    2015-03-24

    The optical navigational control strategy used to intercept moving targets was explored using a real-world object that travels along complex, evasive pathways. Fielders ran across a gymnasium attempting to catch a moving robot that varied in speed and direction, while ongoing position was measured using an infrared motion-capture system. Fielder running paths were compared with the predictions of three lateral control models, each based on maintaining a particular optical angle relative to the robotic target: (a) constant alignment angle (CAA), (b) constant eccentricity angle (CEA), and (c) linear optical trajectory (LOT). Findings reveal that running pathways were most consistent with maintenance of LOT and least consistent with CEA. This supports that fielders use the same optical control strategy of maintaining angular constancy using a LOT when navigating toward targets moving along complex pathways as when intercepting simple ballistic trajectories. In those cases in which a target dramatically deviates from its optical path, fielders appear to simply reset LOT parameters using a new constant angle value. Maintenance of such optical angular constancy has now been shown to work well with ballistic, complex, and evasive moving targets, confirming the LOT strategy as a robust, general-purpose optical control mechanism for navigating to intercept catchable targets, both airborne and ground based.

  1. Development of a Reference System for the determination of the personal dose equivalent and the constancy of X- Ray beams

    International Nuclear Information System (INIS)

    A reference system for the determination of the personal dose equivalent, Hp (10), and a quality control program of X-ray equipment used In radioprotection require the periodic verification of the X-ray beams constancy. In this work, two parallel-plate ionization chambers were developed with inner electrodes of different materials, and inserted into PMMA slab phantoms. One ionization chamber was developed with inner carbon electrodes and the other with inner aluminium electrodes. The two ionization chambers can be used as a Tandem system. The different energy response of the two ionization chambers allowed the development of the Tandem system that is very useful for the checking of the constancy of beam qualities. Standard intermediary energy X-ray beams (from 48 keV to 118 keV), radioprotection level, were established through the development of a dosimetric methodology and the analysis of their physical parameters. The ionization chambers were studied in relation to their operational characteristics, and they were calibrated in X-ray beams (radioprotection, diagnostic radiology, mammography and radiotherapy levels) in accordance to international recommendations. They presented good performance. The determination procedure of personal dose equivalent, Hp (10), was established. (author)

  2. Color features for dating historical color images

    OpenAIRE

    Fernando, Basura; Muselet, Damien; Khan, Rahat; Tuytelaars, Tinne

    2014-01-01

    Fernando B., Muselet D., Khan R., Tuytelaars T., ''Color features for dating historical color image'', IEEE international conference on image processing - ICIP 2014, 5 pp., October 27-30, 2014, Paris, France.

  3. Embedding Color Watermarks in Color Images

    Directory of Open Access Journals (Sweden)

    Wu Tung-Lin

    2003-01-01

    Full Text Available Robust watermarking with oblivious detection is essential to practical copyright protection of digital images. Effective exploitation of the characteristics of human visual perception to color stimuli helps to develop the watermarking scheme that fills the requirement. In this paper, an oblivious watermarking scheme that embeds color watermarks in color images is proposed. Through color gamut analysis and quantizer design, color watermarks are embedded by modifying quantization indices of color pixels without resulting in perceivable distortion. Only a small amount of information including the specification of color gamut, quantizer stepsize, and color tables is required to extract the watermark. Experimental results show that the proposed watermarking scheme is computationally simple and quite robust in face of various attacks such as cropping, low-pass filtering, white-noise addition, scaling, and JPEG compression with high compression ratios.

  4. Auditory hallucinations suppressed by etizolam in a patient with schizophrenia.

    Science.gov (United States)

    Benazzi, F; Mazzoli, M; Rossi, E

    1993-10-01

    A patient presented with a 15 year history of schizophrenia with auditory hallucinations. Though unresponsive to prolonged trials of neuroleptics, the auditory hallucinations disappeared with etizolam. PMID:7902201

  5. Auditory Association Cortex Lesions Impair Auditory Short-Term Memory in Monkeys

    Science.gov (United States)

    Colombo, Michael; D'Amato, Michael R.; Rodman, Hillary R.; Gross, Charles G.

    1990-01-01

    Monkeys that were trained to perform auditory and visual short-term memory tasks (delayed matching-to-sample) received lesions of the auditory association cortex in the superior temporal gyrus. Although visual memory was completely unaffected by the lesions, auditory memory was severely impaired. Despite this impairment, all monkeys could discriminate sounds closer in frequency than those used in the auditory memory task. This result suggests that the superior temporal cortex plays a role in auditory processing and retention similar to the role the inferior temporal cortex plays in visual processing and retention.

  6. Urine - abnormal color

    Science.gov (United States)

    ... medlineplus.gov/ency/article/003139.htm Urine - abnormal color To use the sharing features on this page, please enable JavaScript. The usual color of urine is straw-yellow. Abnormally colored urine ...

  7. Unit 50 - Color

    OpenAIRE

    Unit 57, CC in GIS; Kimerling, Jon

    1990-01-01

    This unit presents an overview of topics related to color, including its physical basis, human visual perception, how color is generated by a CRT and created on paper and how color is measured and specified.

  8. LED Color Characteristics

    Energy Technology Data Exchange (ETDEWEB)

    None

    2012-01-01

    Color quality is an important consideration when evaluating LED-based products for general illumination. This fact sheet reviews the basics regarding light and color and summarizes the most important color issues related to white-light LED systems.

  9. Narrow, duplicated internal auditory canal

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, T. [Servico de Neurorradiologia, Hospital Garcia de Orta, Avenida Torrado da Silva, 2801-951, Almada (Portugal); Shayestehfar, B. [Department of Radiology, UCLA Oliveview School of Medicine, Los Angeles, California (United States); Lufkin, R. [Department of Radiology, UCLA School of Medicine, Los Angeles, California (United States)

    2003-05-01

    A narrow internal auditory canal (IAC) constitutes a relative contraindication to cochlear implantation because it is associated with aplasia or hypoplasia of the vestibulocochlear nerve or its cochlear branch. We report an unusual case of a narrow, duplicated IAC, divided by a bony septum into a superior relatively large portion and an inferior stenotic portion, in which we could identify only the facial nerve. This case adds support to the association between a narrow IAC and aplasia or hypoplasia of the vestibulocochlear nerve. The normal facial nerve argues against the hypothesis that the narrow IAC is the result of a primary bony defect which inhibits the growth of the vestibulocochlear nerve. (orig.)

  10. Auditory hallucinations in nonverbal quadriplegics.

    Science.gov (United States)

    Hamilton, J

    1985-11-01

    When a system for communicating with nonverbal, quadriplegic, institutionalized residents was developed, it was discovered that many were experiencing auditory hallucinations. Nine cases are presented in this study. The "voices" described have many similar characteristics, the primary one being that they give authoritarian commands that tell the residents how to behave and to which the residents feel compelled to respond. Both the relationship of this phenomenon to the theoretical work of Julian Jaynes and its effect on the lives of the residents are discussed.

  11. Autosomal recessive hereditary auditory neuropathy

    Institute of Scientific and Technical Information of China (English)

    王秋菊; 顾瑞; 曹菊阳

    2003-01-01

    Objectives: Auditory neuropathy (AN) is a sensorineural hearing disorder characterized by absent or abnormal auditory brainstem responses (ABRs) and normal cochlear outer hair cell function as measured by otoacoustic emissions (OAEs). Many risk factors are thought to be involved in its etiology and pathophysiology. Three Chinese pedigrees with familial AN are presented herein to demonstrate involvement of genetic factors in AN etiology. Methods: Probands of the above - mentioned pedigrees, who had been diagnosed with AN, were evaluated and followed up in the Department of Otolaryngology Head and Neck Surgery, China PLA General Hospital. Their family members were studied and the pedigree diagrams were established. History of illness, physical examination,pure tone audiometry, acoustic reflex, ABRs and transient evoked and distortion- product otoacoustic emissions (TEOAEs and DPOAEs) were obtained from members of these families. DPOAE changes under the influence of contralateral sound stimuli were observed by presenting a set of continuous white noise to the non - recording ear to exam the function of auditory efferent system. Some subjects received vestibular caloric test, computed tomography (CT)scan of the temporal bone and electrocardiography (ECG) to exclude other possible neuropathy disorders. Results: In most affected subjects, hearing loss of various degrees and speech discrimination difficulties started at 10 to16 years of age. Their audiological evaluation showed absence of acoustic reflex and ABRs. As expected in AN, these subjects exhibited near normal cochlear outer hair cell function as shown in TEOAE & DPOAE recordings. Pure- tone audiometry revealed hearing loss ranging from mild to severe in these patients. Autosomal recessive inheritance patterns were observed in the three families. In Pedigree Ⅰ and Ⅱ, two affected brothers were found respectively, while in pedigree Ⅲ, 2 sisters were affected. All the patients were otherwise normal without

  12. Project Report: Reducing Color Rivalry in Imagery for Conjugated Multiple Bandpass Filter Based Stereo Endoscopy

    Science.gov (United States)

    Ream, Allen

    2011-01-01

    A pair of conjugated multiple bandpass filters (CMBF) can be used to create spatially separated pupils in a traditional lens and imaging sensor system allowing for the passive capture of stereo video. This method is especially useful for surgical endoscopy where smaller cameras are needed to provide ample room for manipulating tools while also granting improved visualizations of scene depth. The significant issue in this process is that, due to the complimentary nature of the filters, the colors seen through each filter do not match each other, and also differ from colors as seen under a white illumination source. A color correction model was implemented that included optimized filter selection, such that the degree of necessary post-processing correction was minimized, and a chromatic adaptation transformation that attempted to fix the imaged colors tristimulus indices based on the principle of color constancy. Due to fabrication constraints, only dual bandpass filters were feasible. The theoretical average color error after correction between these filters was still above the fusion limit meaning that rivalry conditions are possible during viewing. This error can be minimized further by designing the filters for a subset of colors corresponding to specific working environments.

  13. Digital color imaging

    CERN Document Server

    Fernandez-Maloigne, Christine; Macaire, Ludovic

    2013-01-01

    This collective work identifies the latest developments in the field of the automatic processing and analysis of digital color images.For researchers and students, it represents a critical state of the art on the scientific issues raised by the various steps constituting the chain of color image processing.It covers a wide range of topics related to computational color imaging, including color filtering and segmentation, color texture characterization, color invariant for object recognition, color and motion analysis, as well as color image and video indexing and retrieval. <

  14. Further Evidence of Auditory Extinction in Aphasia

    Science.gov (United States)

    Marshall, Rebecca Shisler; Basilakos, Alexandra; Love-Myers, Kim

    2013-01-01

    Purpose: Preliminary research ( Shisler, 2005) suggests that auditory extinction in individuals with aphasia (IWA) may be connected to binding and attention. In this study, the authors expanded on previous findings on auditory extinction to determine the source of extinction deficits in IWA. Method: Seventeen IWA (M[subscript age] = 53.19 years)…

  15. Mapping tonotopy in human auditory cortex

    NARCIS (Netherlands)

    van Dijk, Pim; Langers, Dave R M; Moore, BCJ; Patterson, RD; Winter, IM; Carlyon, RP; Gockel, HE

    2013-01-01

    Tonotopy is arguably the most prominent organizational principle in the auditory pathway. Nevertheless, the layout of tonotopic maps in humans is still debated. We present neuroimaging data that robustly identify multiple tonotopic maps in the bilateral auditory cortex. In contrast with some earlier

  16. Auditory Processing Disorder and Foreign Language Acquisition

    Science.gov (United States)

    Veselovska, Ganna

    2015-01-01

    This article aims at exploring various strategies for coping with the auditory processing disorder in the light of foreign language acquisition. The techniques relevant to dealing with the auditory processing disorder can be attributed to environmental and compensatory approaches. The environmental one involves actions directed at creating a…

  17. Speech perception as complex auditory categorization

    Science.gov (United States)

    Holt, Lori L.

    2002-05-01

    Despite a long and rich history of categorization research in cognitive psychology, very little work has addressed the issue of complex auditory category formation. This is especially unfortunate because the general underlying cognitive and perceptual mechanisms that guide auditory category formation are of great importance to understanding speech perception. I will discuss a new methodological approach to examining complex auditory category formation that specifically addresses issues relevant to speech perception. This approach utilizes novel nonspeech sound stimuli to gain full experimental control over listeners' history of experience. As such, the course of learning is readily measurable. Results from this methodology indicate that the structure and formation of auditory categories are a function of the statistical input distributions of sound that listeners hear, aspects of the operating characteristics of the auditory system, and characteristics of the perceptual categorization system. These results have important implications for phonetic acquisition and speech perception.

  18. Effect of complex treatment using visual and auditory stimuli on the symptoms of attention deficit/hyperactivity disorder in children.

    Science.gov (United States)

    Park, Mi-Sook; Byun, Ki-Won; Park, Yong-Kyung; Kim, Mi-Han; Jung, Sung-Hwa; Kim, Hong

    2013-04-01

    We investigated the effects of complex treatment using visual and auditory stimuli on the symptoms of attention deficit/hyperactivity disorder (ADHD) in children. Forty-seven male children (7-13 yr old), who were clinically diagnosed with ADHD at the Balance Brain Center in Seoul, Korea, were included in this study. The complex treatment consisted of visual and auditory stimuli, core muscle exercise, targeting ball exercise, ocular motor exercise, and visual motor integration. All subjects completed the complex treatment for 60 min/day, 2-3 times/week for more than 12 weeks. Data regarding visual and auditory reaction time and cognitive function were obtained using the Neurosync program, Stroop Color-Word Test, and test of nonverbal intelligence (TONI) at pre- and post-treatment. The complex treatment significantly decreased the total reaction time, while it increased the number of combo actions on visual and auditory stimuli (PStroop color, word, and color-word scores were significantly increased at post-treatment compared to the scores at pretreatment (Peffective ADHD intervention. PMID:24278878

  19. Color grading and colors in film

    OpenAIRE

    Výbora, Jan

    2016-01-01

    This thesis focuses on use of colors in film industry and the possibilities of color grading. It examines manipulation with colors in film history, and examines color theory, which in- cludes their use, meanings and ways of combining them. Next, it maps common visuals styles used in film industry and compares how frequently they are used. With the help of all gathered knowledge, it presents few ways how to color grade in DaVinci Resolve software to achieve desired look. The outcome of the col...

  20. Color improves “visual” acuity via sound

    OpenAIRE

    Levy-Tzedek, Shelly; Riemer, Dar; Amedi, Amir

    2014-01-01

    Visual-to-auditory sensory substitution devices (SSDs) convey visual information via sound, with the primary goal of making visual information accessible to blind and visually impaired individuals. We developed the EyeMusic SSD, which transforms shape, location, and color information into musical notes. We tested the “visual” acuity of 23 individuals (13 blind and 10 blindfolded sighted) on the Snellen tumbling-E test, with the EyeMusic. Participants were asked to determine the orientation of...

  1. Tactile feedback improves auditory spatial localization.

    Science.gov (United States)

    Gori, Monica; Vercillo, Tiziana; Sandini, Giulio; Burr, David

    2014-01-01

    Our recent studies suggest that congenitally blind adults have severely impaired thresholds in an auditory spatial bisection task, pointing to the importance of vision in constructing complex auditory spatial maps (Gori et al., 2014). To explore strategies that may improve the auditory spatial sense in visually impaired people, we investigated the impact of tactile feedback on spatial auditory localization in 48 blindfolded sighted subjects. We measured auditory spatial bisection thresholds before and after training, either with tactile feedback, verbal feedback, or no feedback. Audio thresholds were first measured with a spatial bisection task: subjects judged whether the second sound of a three sound sequence was spatially closer to the first or the third sound. The tactile feedback group underwent two audio-tactile feedback sessions of 100 trials, where each auditory trial was followed by the same spatial sequence played on the subject's forearm; auditory spatial bisection thresholds were evaluated after each session. In the verbal feedback condition, the positions of the sounds were verbally reported to the subject after each feedback trial. The no feedback group did the same sequence of trials, with no feedback. Performance improved significantly only after audio-tactile feedback. The results suggest that direct tactile feedback interacts with the auditory spatial localization system, possibly by a process of cross-sensory recalibration. Control tests with the subject rotated suggested that this effect occurs only when the tactile and acoustic sequences are spatially congruent. Our results suggest that the tactile system can be used to recalibrate the auditory sense of space. These results encourage the possibility of designing rehabilitation programs to help blind persons establish a robust auditory sense of space, through training with the tactile modality. PMID:25368587

  2. Tactile feedback improves auditory spatial localization

    Directory of Open Access Journals (Sweden)

    Monica eGori

    2014-10-01

    Full Text Available Our recent studies suggest that congenitally blind adults have severely impaired thresholds in an auditory spatial-bisection task, pointing to the importance of vision in constructing complex auditory spatial maps (Gori et al., 2014. To explore strategies that may improve the auditory spatial sense in visually impaired people, we investigated the impact of tactile feedback on spatial auditory localization in 48 blindfolded sighted subjects. We measured auditory spatial bisection thresholds before and after training, either with tactile feedback, verbal feedback or no feedback. Audio thresholds were first measured with a spatial bisection task: subjects judged whether the second sound of a three sound sequence was spatially closer to the first or the third sound. The tactile-feedback group underwent two audio-tactile feedback sessions of 100 trials, where each auditory trial was followed by the same spatial sequence played on the subject’s forearm; auditory spatial bisection thresholds were evaluated after each session. In the verbal-feedback condition, the positions of the sounds were verbally reported to the subject after each feedback trial. The no-feedback group did the same sequence of trials, with no feedback. Performance improved significantly only after audio-tactile feedback. The results suggest that direct tactile feedback interacts with the auditory spatial localization system, possibly by a process of cross-sensory recalibration. Control tests with the subject rotated suggested that this effect occurs only when the tactile and acoustic sequences are spatially coherent. Our results suggest that the tactile system can be used to recalibrate the auditory sense of space. These results encourage the possibility of designing rehabilitation programs to help blind persons establish a robust auditory sense of space, through training with the tactile modality.

  3. THE EFFECTS OF SALICYLATE ON AUDITORY EVOKED POTENTIAL AMPLITWDE FROM THE AUDITORY CORTEX AND AUDITORY BRAINSTEM

    Institute of Scientific and Technical Information of China (English)

    Brian Sawka; SUN Wei

    2014-01-01

    Tinnitus has often been studied using salicylate in animal models as they are capable of inducing tempo-rary hearing loss and tinnitus. Studies have recently observed enhancement of auditory evoked responses of the auditory cortex (AC) post salicylate treatment which is also shown to be related to tinnitus like behavior in rats. The aim of this study was to observe if enhancements of the AC post salicylate treatment are also present at structures in the brainstem. Four male Sprague Dawley rats with AC implanted electrodes were tested for both AC and auditory brainstem response (ABR) recordings pre and post 250 mg/kg intraperitone-al injections of salicylate. The responses were recorded as the peak to trough amplitudes of P1-N1 (AC), ABR wave V, and ABR waveⅡ. AC responses resulted in statistically significant enhancement of ampli-tude at 2 hours post salicylate with 90 dB stimuli tone bursts of 4, 8, 12, and 20 kHz. Wave V of ABR re-sponses at 90 dB resulted in a statistically significant reduction of amplitude 2 hours post salicylate and a mean decrease of amplitude of 31%for 16 kHz. WaveⅡamplitudes at 2 hours post treatment were signifi-cantly reduced for 4, 12, and 20 kHz stimuli at 90 dB SPL. Our results suggest that the enhancement chang-es of the AC related to salicylate induced tinnitus are generated superior to the level of the inferior colliculus and may originate in the AC.

  4. Temporal auditory processing in elders

    Directory of Open Access Journals (Sweden)

    Azzolini, Vanuza Conceição

    2010-03-01

    Full Text Available Introduction: In the trial of aging all the structures of the organism are modified, generating intercurrences in the quality of the hearing and of the comprehension. The hearing loss that occurs in consequence of this trial occasion a reduction of the communicative function, causing, also, a distance of the social relationship. Objective: Comparing the performance of the temporal auditory processing between elderly individuals with and without hearing loss. Method: The present study is characterized for to be a prospective, transversal and of diagnosis character field work. They were analyzed 21 elders (16 women and 5 men, with ages between 60 to 81 years divided in two groups, a group "without hearing loss"; (n = 13 with normal auditive thresholds or restricted hearing loss to the isolated frequencies and a group "with hearing loss" (n = 8 with neurosensory hearing loss of variable degree between light to moderately severe. Both the groups performed the tests of frequency (PPS and duration (DPS, for evaluate the ability of temporal sequencing, and the test Randon Gap Detection Test (RGDT, for evaluate the temporal resolution ability. Results: It had not difference statistically significant between the groups, evaluated by the tests DPS and RGDT. The ability of temporal sequencing was significantly major in the group without hearing loss, when evaluated by the test PPS in the condition "muttering". This result presented a growing one significant in parallel with the increase of the age group. Conclusion: It had not difference in the temporal auditory processing in the comparison between the groups.

  5. Interracial Contact and Racial Constancy: A Multi-Site Study of Racial Intergroup Bias in 3-5 Year Old Anglo-British Children

    Science.gov (United States)

    Rutland, Adam; Cameron, Lindsey; Bennett, Laura; Ferrell, Jennifer

    2005-01-01

    This paper examined the influence of interracial contact and racial constancy on the racial intergroup bias of young Anglo-British children. This multi-site study was conducted in areas of Great Britain that varied in terms of racial diversity. The study also investigated whether preschool children express bias on positive, but not negative,…

  6. Relationship between Sympathetic Skin Responses and Auditory Hypersensitivity to Different Auditory Stimuli.

    Science.gov (United States)

    Kato, Fumi; Iwanaga, Ryoichiro; Chono, Mami; Fujihara, Saori; Tokunaga, Akiko; Murata, Jun; Tanaka, Koji; Nakane, Hideyuki; Tanaka, Goro

    2014-07-01

    [Purpose] Auditory hypersensitivity has been widely reported in patients with autism spectrum disorders. However, the neurological background of auditory hypersensitivity is currently not clear. The present study examined the relationship between sympathetic nervous system responses and auditory hypersensitivity induced by different types of auditory stimuli. [Methods] We exposed 20 healthy young adults to six different types of auditory stimuli. The amounts of palmar sweating resulting from the auditory stimuli were compared between groups with (hypersensitive) and without (non-hypersensitive) auditory hypersensitivity. [Results] Although no group × type of stimulus × first stimulus interaction was observed for the extent of reaction, significant type of stimulus × first stimulus interaction was noted for the extent of reaction. For an 80 dB-6,000 Hz stimulus, the trends for palmar sweating differed between the groups. For the first stimulus, the variance became larger in the hypersensitive group than in the non-hypersensitive group. [Conclusion] Subjects who regularly felt excessive reactions to auditory stimuli tended to have excessive sympathetic responses to repeated loud noises compared with subjects who did not feel excessive reactions. People with auditory hypersensitivity may be classified into several subtypes depending on their reaction patterns to auditory stimuli.

  7. Facts About Color Blindness

    Science.gov (United States)

    ... quickly diagnose specific types of color blindness. The Ishihara Color Test is the most common test for red-green ... red-green color blindness. The newer Cambridge Color Test uses a visual array similar to the Ishihara plates, except displayed on a computer monitor. The ...

  8. Texture affects color emotion

    NARCIS (Netherlands)

    M.P. Lucassen; T. Gevers; A. Gijsenij

    2011-01-01

    Several studies have recorded color emotions in subjects viewing uniform color (UC) samples. We conduct an experiment to measure and model how these color emotions change when texture is added to the color samples. Using a computer monitor, our subjects arrange samples along four scales: warm-cool,

  9. Color Me Understood.

    Science.gov (United States)

    Harris, Judy J.

    2000-01-01

    Describes the "color system" as a way of grouping children into different personality types based on a certain color: orange, blue, green, and gold. Lists stress producers for specific color people. Asserts that, through making groups of different colors, children begin to see the various specialties others can bring to the group and learn to…

  10. Industrial Color Physics

    CERN Document Server

    Klein, Georg A

    2010-01-01

    This unique book starts with a short historical overview of the development of the theories of color vision and applications of industrial color physics. The three dominant factors producing color - light source, color sample, and observer - are described in detail. The standardized color spaces are shown and related color values are applied to characteristic color qualities of absorption as well as of effect colorants. The fundamentals of spectrometric and colorimetric measuring techniques together with specific applications are described. Theoretical models for radiative transfer in transparent, translucent, and opaque layers are detailed; the two, three, and multi-flux approximations are presented for the first time in a coherent formalism. These methods constitute the fundamentals not only for the important classical methods, but also modern methods of recipe prediction applicable to all known colorants. The text is supplied with 52 tables, more than 200 partially colored illustrations, an appendix, and a...

  11. Spatial auditory processing in pinnipeds

    Science.gov (United States)

    Holt, Marla M.

    Given the biological importance of sound for a variety of activities, pinnipeds must be able to obtain spatial information about their surroundings thorough acoustic input in the absence of other sensory cues. The three chapters of this dissertation address spatial auditory processing capabilities of pinnipeds in air given that these amphibious animals use acoustic signals for reproduction and survival on land. Two chapters are comparative lab-based studies that utilized psychophysical approaches conducted in an acoustic chamber. Chapter 1 addressed the frequency-dependent sound localization abilities at azimuth of three pinniped species (the harbor seal, Phoca vitulina, the California sea lion, Zalophus californianus, and the northern elephant seal, Mirounga angustirostris). While performances of the sea lion and harbor seal were consistent with the duplex theory of sound localization, the elephant seal, a low-frequency hearing specialist, showed a decreased ability to localize the highest frequencies tested. In Chapter 2 spatial release from masking (SRM), which occurs when a signal and masker are spatially separated resulting in improvement in signal detectability relative to conditions in which they are co-located, was determined in a harbor seal and sea lion. Absolute and masked thresholds were measured at three frequencies and azimuths to determine the detection advantages afforded by this type of spatial auditory processing. Results showed that hearing sensitivity was enhanced by up to 19 and 12 dB in the harbor seal and sea lion, respectively, when the signal and masker were spatially separated. Chapter 3 was a field-based study that quantified both sender and receiver variables of the directional properties of male northern elephant seal calls produce within communication system that serves to delineate dominance status. This included measuring call directivity patterns, observing male-male vocally-mediated interactions, and an acoustic playback study

  12. An Auditory Model of Improved Adaptive ZCPA

    Directory of Open Access Journals (Sweden)

    Jinping Zhang

    2013-07-01

    Full Text Available An improved ZCAP auditory model with adaptability is proposed in this paper, and the  adaptive method designed for ZCPA model is suitable for other auditory model with inner-hair-cell sub-model. The first step in the implement process of the proposed ZCPA model is to carry out the calculation of inner product between signal and complex Gammatone filters to obtain important frequency components  of signal. And then, according to  the result of the first step, the parameters of the basilar membrane sub-model and frequency box are automatically adjusted, such as the number of the basilar membrane filters, center frequency and bandwith of each basilar membrane filter, position of each frequency box, and so on. Lastly  an auditory model is built, and the final output is auditory spectrum.The results of numerical simulation and experiments have showed that the proposed model could realize accurate frequency selection, and the auditory spectrum is more distinctly than that of conventional ZCPA model. Moreover, the proposed model can completely avoided the influence of the number of filter on the shape of auditory spectrum existing in conventional ZCPA model so that the shape of auditory spectrum is steady, and the data quantity is small.

  13. Auditory Efferent System Modulates Mosquito Hearing.

    Science.gov (United States)

    Andrés, Marta; Seifert, Marvin; Spalthoff, Christian; Warren, Ben; Weiss, Lukas; Giraldo, Diego; Winkler, Margret; Pauls, Stephanie; Göpfert, Martin C

    2016-08-01

    The performance of vertebrate ears is controlled by auditory efferents that originate in the brain and innervate the ear, synapsing onto hair cell somata and auditory afferent fibers [1-3]. Efferent activity can provide protection from noise and facilitate the detection and discrimination of sound by modulating mechanical amplification by hair cells and transmitter release as well as auditory afferent action potential firing [1-3]. Insect auditory organs are thought to lack efferent control [4-7], but when we inspected mosquito ears, we obtained evidence for its existence. Antibodies against synaptic proteins recognized rows of bouton-like puncta running along the dendrites and axons of mosquito auditory sensory neurons. Electron microscopy identified synaptic and non-synaptic sites of vesicle release, and some of the innervating fibers co-labeled with somata in the CNS. Octopamine, GABA, and serotonin were identified as efferent neurotransmitters or neuromodulators that affect auditory frequency tuning, mechanical amplification, and sound-evoked potentials. Mosquito brains thus modulate mosquito ears, extending the use of auditory efferent systems from vertebrates to invertebrates and adding new levels of complexity to mosquito sound detection and communication. PMID:27476597

  14. The road coloring problem

    OpenAIRE

    Trahtman, A. N.

    2007-01-01

    The synchronizing word of deterministic automaton is a word in the alphabet of colors (considered as letters) of its edges that maps the automaton to a single state. A coloring of edges of a directed graph is synchronizing if the coloring turns the graph into deterministic finite automaton possessing a synchronizing word. The road coloring problem is a problem of synchronizing coloring of directed finite strongly connected graph with constant outdegree of all its vertices if the greatest comm...

  15. Impact of submerged aquatic macrophytes on 3-dim current systems and hydrodynamic transport processes in Lake Constance

    Science.gov (United States)

    Wolf, Thomas; Lüddeke, Frauke; Thiange, Christophe

    2015-04-01

    According to the assessment criteria of the European water framework directive Lake Constance is having a good water quality. Nevertheless upcoming criteria using environmental quality measures show that there are still problems with respect to micropollutants. In fact, we observe significantly enhanced concentrations of micropollutants close to river mouths and in the areas of shallow water zones within Lake Constance compared to deep water concentrations. These findings are caused by river water plumes which can flow over distances of kilometers in the lake without being diluted or mixed only weakly with the surrounding lake water body. Besides, in the area of interest exist large populations of submerged aquatic macrophytes (SAM). There is only little knowledge, how these influence the distribution and transport processes of micropollutants. In order to assess the impact and distribution of river water plumes in different areas of the lake we implemented a 3-dim hydrodynamic model using DELFT3D-FLOW on a locally refined numerical grid which enables to cover different process scales of the distribution of river water bodies ranging from a few meters up to basin wide scales in the order of a few kilometers. We used numerical tracers (conservative and non-conservative) in order to quantify the impact of different abstract substance classes which are distinguished by their decay rates. In order to asses the influence of SAM populations on current field and transport processes we used a special simulation technique - the trachytope concept. The results of our 3-dim hydrodynamic model showed significantly changed current velocities, residence times and age of water parameters within the SAM areas compared to the control simulation without SAM. By simulating the propagation of coliform bacteria using numerical tracers with spatially and temporarily variable decay rates, we found complex impact pattern of the SAM on the distribution of these potentially harmful

  16. Functional Neurochemistry of the Auditory System

    Directory of Open Access Journals (Sweden)

    Nourollah Agha Ebrahimi

    1993-03-01

    Full Text Available Functional Neurochemistry is one of the fields of studies in the auditory system which has had an outstanding development in the recent years. Many of the findings in the mentioned field had led not only the basic auditory researches but also the clinicians to new points of view in audiology.Here, we are aimed at discussing the latest investigations in the Functional Neurochemistry of the auditory system and have focused this review mainly on the researches which will arise flashes of hope for future clinical studies

  17. Auditory Neuropathy/Dyssynchrony in Biotinidase Deficiency

    Science.gov (United States)

    Yaghini, Omid

    2016-01-01

    Biotinidase deficiency is a disorder inherited autosomal recessively showing evidence of hearing loss and optic atrophy in addition to seizures, hypotonia, and ataxia. In the present study, a 2-year-old boy with Biotinidase deficiency is presented in which clinical symptoms have been reported with auditory neuropathy/auditory dyssynchrony (AN/AD). In this case, transient-evoked otoacoustic emissions showed bilaterally normal responses representing normal function of outer hair cells. In contrast, acoustic reflex test showed absent reflexes bilaterally, and visual reinforcement audiometry and auditory brainstem responses indicated severe to profound hearing loss in both ears. These results suggest AN/AD in patients with Biotinidase deficiency. PMID:27144235

  18. Functional Neurochemistry of the Auditory System

    OpenAIRE

    Nourollah Agha Ebrahimi

    1993-01-01

    Functional Neurochemistry is one of the fields of studies in the auditory system which has had an outstanding development in the recent years. Many of the findings in the mentioned field had led not only the basic auditory researches but also the clinicians to new points of view in audiology.Here, we are aimed at discussing the latest investigations in the Functional Neurochemistry of the auditory system and have focused this review mainly on the researches which will arise flashes of hope f...

  19. Auditory filters at low-frequencies

    DEFF Research Database (Denmark)

    Orellana, Carlos Andrés Jurado; Pedersen, Christian Sejer; Møller, Henrik

    2009-01-01

    Prediction and assessment of low-frequency noise problems requires information about the auditory filter characteristics at low-frequencies. Unfortunately, data at low-frequencies is scarce and practically no results have been published for frequencies below 100 Hz. Extrapolation of ERB results......-ear transfer function), the asymmetry of the auditory filter changed from steeper high-frequency slopes at 1000 Hz to steeper low-frequency slopes below 100 Hz. Increasing steepness at low-frequencies of the middle-ear high-pass filter is thought to cause this effect. The dynamic range of the auditory filter...

  20. Assessing the aging effect on auditory-verbal memory by Persian version of dichotic auditory verbal memory test

    Directory of Open Access Journals (Sweden)

    Zahra Shahidipour

    2014-01-01

    Conclusion: Based on the obtained results, significant reduction in auditory memory was seen in aged group and the Persian version of dichotic auditory-verbal memory test, like many other auditory verbal memory tests, showed the aging effects on auditory verbal memory performance.

  1. AUDITORY CORTICAL PLASTICITY: DOES IT PROVIDE EVIDENCE FOR COGNITIVE PROCESSING IN THE AUDITORY CORTEX?

    OpenAIRE

    Irvine, Dexter R. F.

    2007-01-01

    The past 20 years have seen substantial changes in our view of the nature of the processing carried out in auditory cortex. Some processing of a cognitive nature, previously attributed to higher order “association” areas, is now considered to take place in auditory cortex itself. One argument adduced in support of this view is the evidence indicating a remarkable degree of plasticity in the auditory cortex of adult animals. Such plasticity has been demonstrated in a wide range of paradigms, i...

  2. Frequency band-importance functions for auditory and auditory-visual speech recognition

    Science.gov (United States)

    Grant, Ken W.

    2005-04-01

    In many everyday listening environments, speech communication involves the integration of both acoustic and visual speech cues. This is especially true in noisy and reverberant environments where the speech signal is highly degraded, or when the listener has a hearing impairment. Understanding the mechanisms involved in auditory-visual integration is a primary interest of this work. Of particular interest is whether listeners are able to allocate their attention to various frequency regions of the speech signal differently under auditory-visual conditions and auditory-alone conditions. For auditory speech recognition, the most important frequency regions tend to be around 1500-3000 Hz, corresponding roughly to important acoustic cues for place of articulation. The purpose of this study is to determine the most important frequency region under auditory-visual speech conditions. Frequency band-importance functions for auditory and auditory-visual conditions were obtained by having subjects identify speech tokens under conditions where the speech-to-noise ratio of different parts of the speech spectrum is independently and randomly varied on every trial. Point biserial correlations were computed for each separate spectral region and the normalized correlations are interpreted as weights indicating the importance of each region. Relations among frequency-importance functions for auditory and auditory-visual conditions will be discussed.

  3. In search of an auditory engram

    Science.gov (United States)

    Fritz, Jonathan; Mishkin, Mortimer; Saunders, Richard C.

    2005-01-01

    Monkeys trained preoperatively on a task designed to assess auditory recognition memory were impaired after removal of either the rostral superior temporal gyrus or the medial temporal lobe but were unaffected by lesions of the rhinal cortex. Behavioral analysis indicated that this result occurred because the monkeys did not or could not use long-term auditory recognition, and so depended instead on short-term working memory, which is unaffected by rhinal lesions. The findings suggest that monkeys may be unable to place representations of auditory stimuli into a long-term store and thus question whether the monkey's cerebral memory mechanisms in audition are intrinsically different from those in other sensory modalities. Furthermore, it raises the possibility that language is unique to humans not only because it depends on speech but also because it requires long-term auditory memory. PMID:15967995

  4. Effect of omega-3 on auditory system

    Directory of Open Access Journals (Sweden)

    Vida Rahimi

    2014-01-01

    Full Text Available Background and Aim: Omega-3 fatty acid have structural and biological roles in the body 's various systems . Numerous studies have tried to research about it. Auditory system is affected a s well. The aim of this article was to review the researches about the effect of omega-3 on auditory system.Methods: We searched Medline , Google Scholar, PubMed, Cochrane Library and SID search engines with the "auditory" and "omega-3" keywords and read textbooks about this subject between 19 70 and 20 13.Conclusion: Both excess and deficient amounts of dietary omega-3 fatty acid can cause harmful effects on fetal and infant growth and development of brain and central nervous system esspesially auditory system. It is important to determine the adequate dosage of omega-3.

  5. Auditory perception modulated by word reading.

    Science.gov (United States)

    Cao, Liyu; Klepp, Anne; Schnitzler, Alfons; Gross, Joachim; Biermann-Ruben, Katja

    2016-10-01

    Theories of embodied cognition positing that sensorimotor areas are indispensable during language comprehension are supported by neuroimaging and behavioural studies. Among others, the auditory system has been suggested to be important for understanding sound-related words (visually presented) and the motor system for action-related words. In this behavioural study, using a sound detection task embedded in a lexical decision task, we show that in participants with high lexical decision performance sound verbs improve auditory perception. The amount of modulation was correlated with lexical decision performance. Our study provides convergent behavioural evidence of auditory cortex involvement in word processing, supporting the view of embodied language comprehension concerning the auditory domain. PMID:27324193

  6. [Approaches to therapy of auditory agnosia].

    Science.gov (United States)

    Fechtelpeter, A; Göddenhenrich, S; Huber, W; Springer, L

    1990-01-01

    In a 41-year-old stroke patient with bitemporal brain damage, we found severe signs of auditory agnosia 6 months after onset. Recognition of environmental sounds was extremely impaired when tested in a multiple choice sound-picture matching task, whereas auditory discrimination between sounds and picture identifications by written names was almost undisturbed. In a therapy experiment, we tried to enhance sound recognition via semantic categorization and association, imitation of sound and analysis of auditory features, respectively. The stimulation of conscious auditory analysis proved to be increasingly effective over a 4-week period of therapy. We were able to show that the patient's improvement was not only a simple effect of practicing, but it was stable and carried over to nontrained items.

  7. Auditory-visual spatial interaction and modularity

    Science.gov (United States)

    Radeau, M

    1994-02-01

    The results of dealing with the conditions for pairing visual and auditory data coming from spatially separate locations argue for cognitive impenetrability and computational autonomy, the pairing rules being the Gestalt principles of common fate and proximity. Other data provide evidence for pairing with several properties of modular functioning. Arguments for domain specificity are inferred from comparison with audio-visual speech. Suggestion of innate specification can be found in developmental data indicating that the grouping of visual and auditory signals is supported very early in life by the same principles that operate in adults. Support for a specific neural architecture comes from neurophysiological studies of the bimodal (auditory-visual) neurons of the cat superior colliculus. Auditory-visual pairing thus seems to present the four main properties of the Fodorian module.

  8. Auditory stimulation and cardiac autonomic regulation

    Directory of Open Access Journals (Sweden)

    Vitor E. Valenti

    2012-08-01

    Full Text Available Previous studies have already demonstrated that auditory stimulation with music influences the cardiovascular system. In this study, we described the relationship between musical auditory stimulation and heart rate variability. Searches were performed with the Medline, SciELO, Lilacs and Cochrane databases using the following keywords: "auditory stimulation", "autonomic nervous system", "music" and "heart rate variability". The selected studies indicated that there is a strong correlation between noise intensity and vagal-sympathetic balance. Additionally, it was reported that music therapy improved heart rate variability in anthracycline-treated breast cancer patients. It was hypothesized that dopamine release in the striatal system induced by pleasurable songs is involved in cardiac autonomic regulation. Musical auditory stimulation influences heart rate variability through a neural mechanism that is not well understood. Further studies are necessary to develop new therapies to treat cardiovascular disorders.

  9. Environment for Auditory Research Facility (EAR)

    Data.gov (United States)

    Federal Laboratory Consortium — EAR is an auditory perception and communication research center enabling state-of-the-art simulation of various indoor and outdoor acoustic environments. The heart...

  10. Auditory sequence analysis and phonological skill

    OpenAIRE

    Grube, Manon; Kumar, Sukhbinder; Cooper, Freya E.; Turton, Stuart; Griffiths, Timothy D

    2012-01-01

    This work tests the relationship between auditory and phonological skill in a non-selected cohort of 238 school students (age 11) with the specific hypothesis that sound-sequence analysis would be more relevant to phonological skill than the analysis of basic, single sounds. Auditory processing was assessed across the domains of pitch, time and timbre; a combination of six standard tests of literacy and language ability was used to assess phonological skill. A significant correlation between ...

  11. Auditory memory function in expert chess players

    OpenAIRE

    Fattahi, Fariba; Geshani, Ahmad; Jafari, Zahra; Jalaie, Shohreh; Salman Mahini, Mona

    2015-01-01

    Background: Chess is a game that involves many aspects of high level cognition such as memory, attention, focus and problem solving. Long term practice of chess can improve cognition performances and behavioral skills. Auditory memory, as a kind of memory, can be influenced by strengthening processes following long term chess playing like other behavioral skills because of common processing pathways in the brain. The purpose of this study was to evaluate the auditory memory function of expert...

  12. Auditory brain-stem responses in syphilis.

    OpenAIRE

    Rosenhall, U; Roupe, G

    1981-01-01

    Analysis of auditory brain-stem electrical responses (BSER) provides an effective means of detecting lesions in the auditory pathways. In the present study the wave patterns were analysed in 11 patients with secondary or latent syphilis with no clinical symptoms referrable to the central nervous system and in two patients with congenital syphilis and general paralysis. Decreased amplitudes and prolonged latencies occurred frequently in patients with secondary and with advanced syphilis. This ...

  13. Auditory model inversion and its application

    Institute of Scientific and Technical Information of China (English)

    ZHAO Heming; WANG Yongqi; CHEN Xueqin

    2005-01-01

    Auditory model has been applied to several aspects of speech signal processing field, and appears to be effective in performance. This paper presents the inverse transform of each stage of one widely used auditory model. First of all it is necessary to invert correlogram and reconstruct phase information by repetitious iterations in order to get auditory-nerve firing rate. The next step is to obtain the negative parts of the signal via the reverse process of the HWR (Half Wave Rectification). Finally the functions of inner hair cell/synapse model and Gammatone filters have to be inverted. Thus the whole auditory model inversion has been achieved. An application of noisy speech enhancement based on auditory model inversion algorithm is proposed. Many experiments show that this method is effective in reducing noise.Especially when SNR of noisy speech is low it is more effective than other methods. Thus this auditory model inversion method given in this paper is applicable to speech enhancement field.

  14. Color vision: retinal blues.

    Science.gov (United States)

    Johnston, Jamie; Esposti, Federico; Lagnado, Leon

    2012-08-21

    Two complementary studies have resolved the circuitry underlying green-blue color discrimination in the retina. A blue-sensitive interneuron provides the inhibitory signal required for computing green-blue color opponency.

  15. Color chiral solitons

    CERN Document Server

    Novozhilov, V Yu; Novozhilov, Victor; Novozhilov, Yuri

    2002-01-01

    We discuss specific features of color chiral solitons (asymptotics, possibility of confainment, quantization) at example of isolated SU(2) color skyrmions, i.e. skyrmions in a background field which is the vacuum field forming the gluon condensate.

  16. Colors Can Affect Us!

    Institute of Scientific and Technical Information of China (English)

    张俊斌

    2006-01-01

    Different colors affect us differently.The following will show us how they work. Experiment proves that math problems worked on yellow paper have fewer mistakes than problems written on other colors of paper.

  17. Color rendition engine.

    Science.gov (United States)

    Zukauskas, Artūras; Vaicekauskas, Rimantas; Vitta, Pranciškus; Tuzikas, Arūnas; Petrulis, Andrius; Shur, Michael

    2012-02-27

    A source of white light with continuously tuned color rendition properties, such as color fidelity, as well as color saturating and color dulling ability has been developed. The source, which is composed of red (R), amber (A), green (G), and blue (B) light-emitting diodes, has a spectral power distribution varied as a weighted sum of "white" RGB and AGB blends. At the RGB and AGB end-points, the source has a highest color saturating and color dulling ability, respectively, as follows from the statistical analysis of the color-shift vectors for 1269 Munsell samples. The variation of the weight parameter allows for continuously traversing all possible metameric RAGB blends, including that with the highest color fidelity. The source was used in a psychophysical experiment on the estimation of the color appearance of familiar objects, such as vegetables, fruits, and soft-drink cans of common brands, at correlated color temperatures of 3000 K, 4500 K, and 6500 K. By continuously tuning the weight parameter, each of 100 subjects selected RAGB blends that, to their opinion, matched lighting characterized as "most saturating," "most dulling," "most natural," and "preferential". The end-point RGB and AGB blends have been almost unambiguously attributed to "most saturating" and "most dulling" lighting, respectively. RAGB blends that render a highest number of colors with high fidelity have, on average, been attributed to "most natural" lighting. The "preferential" color quality of lighting has, on average, been matched to RAGB blends that provide color rendition with fidelity somewhat reduced in favor of a higher saturation. Our results infer that tunable "color rendition engines" can validate color rendition metrics and provide lighting meeting specific needs and preferences to color quality. PMID:22418343

  18. Constance Gunderson, Human trafficking : the trafficking of women in northern Germany for the purpose of sexual exploitation, systematic overview of community based responses and challenges (Bremen: Lit Verlag, 2012)

    OpenAIRE

    Markus Meckl

    2013-01-01

    A review of the following book: Constance Gunderson, Human Trafficking: The Trafficking of Women in Northern Germany for the Purpose of Sexual Exploitation. Systematic Overview of Community based responses and challenges (Bremen: Lit Verlag, Bremen 2012)

  19. Constance Gunderson, Human Trafficking: The Trafficking of Women in Northern Germany for the Purpose of Sexual Exploitation. Systematic Overview of Community Based Responses and Challenges (Bremen: Lit Verlag, 2012

    Directory of Open Access Journals (Sweden)

    Markus Meckl

    2013-03-01

    Full Text Available A review of the following book: Constance Gunderson, Human Trafficking: The Trafficking of Women in Northern Germany for the Purpose of Sexual Exploitation. Systematic Overview of Community based responses and challenges (Bremen: Lit Verlag, Bremen 2012

  20. Reimagining the Color Wheel

    Science.gov (United States)

    Snyder, Jennifer

    2011-01-01

    Color wheels are a traditional project for many teachers. The author has used them in art appreciation classes for many years, but one problem she found when her pre-service art education students created colored wheels was that they were boring: simple circles, with pie-shaped pieces, which students either painted or colored in. This article…

  1. Auditory sustained field responses to periodic noise

    Directory of Open Access Journals (Sweden)

    Keceli Sumru

    2012-01-01

    Full Text Available Abstract Background Auditory sustained responses have been recently suggested to reflect neural processing of speech sounds in the auditory cortex. As periodic fluctuations below the pitch range are important for speech perception, it is necessary to investigate how low frequency periodic sounds are processed in the human auditory cortex. Auditory sustained responses have been shown to be sensitive to temporal regularity but the relationship between the amplitudes of auditory evoked sustained responses and the repetitive rates of auditory inputs remains elusive. As the temporal and spectral features of sounds enhance different components of sustained responses, previous studies with click trains and vowel stimuli presented diverging results. In order to investigate the effect of repetition rate on cortical responses, we analyzed the auditory sustained fields evoked by periodic and aperiodic noises using magnetoencephalography. Results Sustained fields were elicited by white noise and repeating frozen noise stimuli with repetition rates of 5-, 10-, 50-, 200- and 500 Hz. The sustained field amplitudes were significantly larger for all the periodic stimuli than for white noise. Although the sustained field amplitudes showed a rising and falling pattern within the repetition rate range, the response amplitudes to 5 Hz repetition rate were significantly larger than to 500 Hz. Conclusions The enhanced sustained field responses to periodic noises show that cortical sensitivity to periodic sounds is maintained for a wide range of repetition rates. Persistence of periodicity sensitivity below the pitch range suggests that in addition to processing the fundamental frequency of voice, sustained field generators can also resolve low frequency temporal modulations in speech envelope.

  2. Effects of an Auditory Lateralization Training in Children Suspected to Central Auditory Processing Disorder

    Science.gov (United States)

    Lotfi, Yones; Moosavi, Abdollah; Bakhshi, Enayatollah; Sadjedi, Hamed

    2016-01-01

    Background and Objectives Central auditory processing disorder [(C)APD] refers to a deficit in auditory stimuli processing in nervous system that is not due to higher-order language or cognitive factors. One of the problems in children with (C)APD is spatial difficulties which have been overlooked despite their significance. Localization is an auditory ability to detect sound sources in space and can help to differentiate between the desired speech from other simultaneous sound sources. Aim of this research was investigating effects of an auditory lateralization training on speech perception in presence of noise/competing signals in children suspected to (C)APD. Subjects and Methods In this analytical interventional study, 60 children suspected to (C)APD were selected based on multiple auditory processing assessment subtests. They were randomly divided into two groups: control (mean age 9.07) and training groups (mean age 9.00). Training program consisted of detection and pointing to sound sources delivered with interaural time differences under headphones for 12 formal sessions (6 weeks). Spatial word recognition score (WRS) and monaural selective auditory attention test (mSAAT) were used to follow the auditory lateralization training effects. Results This study showed that in the training group, mSAAT score and spatial WRS in noise (p value≤0.001) improved significantly after the auditory lateralization training. Conclusions We used auditory lateralization training for 6 weeks and showed that auditory lateralization can improve speech understanding in noise significantly. The generalization of this results needs further researches.

  3. Zooplankton communities in a large prealpine lake, Lake Constance: comparison between the Upper and the Lower Lake

    Directory of Open Access Journals (Sweden)

    Gerhard MAIER

    2005-08-01

    Full Text Available The zooplankton communities of two basins of a large lake, Lake Constance, were compared during the years 2002 and 2003. The two basins differ in morphology, physical and chemical conditions. The Upper Lake basin has a surface area of 470 km2, a mean depth of 100 and a maximum depth of 250 m; the Lower Lake basin has a surface area of 62 km2, a mean depth of only 13 and a maximum depth of 40 m. Nutrient, chlorophyll-a concentrations and mean temperatures are somewhat higher in the Lower than in the Upper Lake. Total abundance of rotifers (number per m2 lake surface was higher and rotifer development started earlier in the year in the Lower than in the Upper Lake. Total abundance of crustaceans was higher in the Upper Lake in the year 2002; in the year 2003 no difference in abundance could be detected between the lake basins, although in summer crustacean abundance was higher in the Lower than in the Upper Lake. Crustacean communities differed significantly between lake basins while there was no apparent difference in rotifer communities. In the Lower Lake small crustaceans, like Bosmina spp., Ceriodaphnia pulchella and Thermocyclops oithonoides prevailed. Abundance (number per m2 lake surface of predatory cladocerans, large daphnids and large copepods was much lower in the Lower than in the Upper Lake, in particular during the summer months. Ordination with nonmetric multidimensional scaling (NMS separated communities of both lakes along gradients that correlated with temperature and chlorophyll a concentration. Clutches of copepods were larger in the Lower than in the Upper Lake. No difference could be detected in clutch size of large daphnids between lake basins. Our results show that zooplankton communities in different basins of Lake Constance can be very different. They further suggest that the lack of large crustaceans in particular the lack of large predatory cladocerans in the Lower Lake can have negative effects on growth and

  4. Tanslation of Color Words

    Institute of Scientific and Technical Information of China (English)

    徐丹

    2009-01-01

    Being a minor part in the translation field,the translation of color words is far more complex than people may have imagined.Apart from the literal meaning of color words in the target language,there are other factors that affect the understanding.This paper mainly focuses on three main characteristics of color words that make the translation work difficult-color words'variations and combinations,rich symbolic meanings and culture differences.It also provides possible ways to deal with the prickly problem of finding equivalents,the complexity of transferring symbolic meanings and the subtle problem of crossing culture boundaries in translation of color words.

  5. SchussenAktivplus: reduction of micropollutants and of potentially pathogenic bacteria for further water quality improvement of the river Schussen, a tributary of Lake Constance, Germany

    OpenAIRE

    Triebskorn, Rita; Amler, Klaus; BLAHA, Ludek; Gallert, Claudia; Giebner, Sabrina; Güde, Hans; Henneberg, Anja; Hess, Stefanie; Hetzenauer, Harald; Jedele, Klaus; Jung, Ralph-Michael; Kneipp, Sven; Köhler, Heinz-R.; Krais, Stefanie; Kuch, Bertram

    2013-01-01

    The project focuses on the efficiency of combined technologies to reduce the release of micropollutants and bacteria into surface waters via sewage treatment plants of different size and via stormwater overflow basins of different types. As a model river in a highly populated catchment area, the river Schussen and, as a control, the river Argen, two tributaries of Lake Constance, Southern Germany, are under investigation in this project. The efficiency of the different cleaning technologies i...

  6. Interracial contact and racial constancy: A multi-site study of racial intergroup bias in 3-5 year old Anglo-British children

    OpenAIRE

    Rutland, Adam; Cameron, Lindsey; Bennett, Laura; Ferrell, Jennifer M.

    2005-01-01

    This paper examined the influence of interracial contact and racial constancy on the racial intergroup bias of young Anglo-British children. This multi-site study was conducted in areas of Great Britain that varied in terms of racial diversity. The study also investigated whether preschool children express bias on positive, but not negative, valence attributions. Anglo-British children (N = 136) between 3 and 5 years of age with different levels of interracial contact undertook a racial stere...

  7. Auditory and motor imagery modulate learning in music performance

    Science.gov (United States)

    Brown, Rachel M.; Palmer, Caroline

    2013-01-01

    Skilled performers such as athletes or musicians can improve their performance by imagining the actions or sensory outcomes associated with their skill. Performers vary widely in their auditory and motor imagery abilities, and these individual differences influence sensorimotor learning. It is unknown whether imagery abilities influence both memory encoding and retrieval. We examined how auditory and motor imagery abilities influence musicians' encoding (during Learning, as they practiced novel melodies), and retrieval (during Recall of those melodies). Pianists learned melodies by listening without performing (auditory learning) or performing without sound (motor learning); following Learning, pianists performed the melodies from memory with auditory feedback (Recall). During either Learning (Experiment 1) or Recall (Experiment 2), pianists experienced either auditory interference, motor interference, or no interference. Pitch accuracy (percentage of correct pitches produced) and temporal regularity (variability of quarter-note interonset intervals) were measured at Recall. Independent tests measured auditory and motor imagery skills. Pianists' pitch accuracy was higher following auditory learning than following motor learning and lower in motor interference conditions (Experiments 1 and 2). Both auditory and motor imagery skills improved pitch accuracy overall. Auditory imagery skills modulated pitch accuracy encoding (Experiment 1): Higher auditory imagery skill corresponded to higher pitch accuracy following auditory learning with auditory or motor interference, and following motor learning with motor or no interference. These findings suggest that auditory imagery abilities decrease vulnerability to interference and compensate for missing auditory feedback at encoding. Auditory imagery skills also influenced temporal regularity at retrieval (Experiment 2): Higher auditory imagery skill predicted greater temporal regularity during Recall in the presence of

  8. Auditory and motor imagery modulate learning in music performance.

    Science.gov (United States)

    Brown, Rachel M; Palmer, Caroline

    2013-01-01

    Skilled performers such as athletes or musicians can improve their performance by imagining the actions or sensory outcomes associated with their skill. Performers vary widely in their auditory and motor imagery abilities, and these individual differences influence sensorimotor learning. It is unknown whether imagery abilities influence both memory encoding and retrieval. We examined how auditory and motor imagery abilities influence musicians' encoding (during Learning, as they practiced novel melodies), and retrieval (during Recall of those melodies). Pianists learned melodies by listening without performing (auditory learning) or performing without sound (motor learning); following Learning, pianists performed the melodies from memory with auditory feedback (Recall). During either Learning (Experiment 1) or Recall (Experiment 2), pianists experienced either auditory interference, motor interference, or no interference. Pitch accuracy (percentage of correct pitches produced) and temporal regularity (variability of quarter-note interonset intervals) were measured at Recall. Independent tests measured auditory and motor imagery skills. Pianists' pitch accuracy was higher following auditory learning than following motor learning and lower in motor interference conditions (Experiments 1 and 2). Both auditory and motor imagery skills improved pitch accuracy overall. Auditory imagery skills modulated pitch accuracy encoding (Experiment 1): Higher auditory imagery skill corresponded to higher pitch accuracy following auditory learning with auditory or motor interference, and following motor learning with motor or no interference. These findings suggest that auditory imagery abilities decrease vulnerability to interference and compensate for missing auditory feedback at encoding. Auditory imagery skills also influenced temporal regularity at retrieval (Experiment 2): Higher auditory imagery skill predicted greater temporal regularity during Recall in the presence of

  9. Acquired color vision deficiency.

    Science.gov (United States)

    Simunovic, Matthew P

    2016-01-01

    Acquired color vision deficiency occurs as the result of ocular, neurologic, or systemic disease. A wide array of conditions may affect color vision, ranging from diseases of the ocular media through to pathology of the visual cortex. Traditionally, acquired color vision deficiency is considered a separate entity from congenital color vision deficiency, although emerging clinical and molecular genetic data would suggest a degree of overlap. We review the pathophysiology of acquired color vision deficiency, the data on its prevalence, theories for the preponderance of acquired S-mechanism (or tritan) deficiency, and discuss tests of color vision. We also briefly review the types of color vision deficiencies encountered in ocular disease, with an emphasis placed on larger or more detailed clinical investigations.

  10. Effects of Caffeine on Auditory Brainstem Response

    Directory of Open Access Journals (Sweden)

    Saleheh Soleimanian

    2008-06-01

    Full Text Available Background and Aim: Blocking of the adenosine receptor in central nervous system by caffeine can lead to increasing the level of neurotransmitters like glutamate. As the adenosine receptors are present in almost all brain areas like central auditory pathway, it seems caffeine can change conduction in this way. The purpose of this study was to evaluate the effects of caffeine on latency and amplitude of auditory brainstem response(ABR.Materials and Methods: In this clinical trial study 43 normal 18-25 years old male students were participated. The subjects consumed 0, 2 and 3 mg/kg BW caffeine in three different sessions. Auditory brainstem responses were recorded before and 30 minute after caffeine consumption. The results were analyzed by Friedman and Wilcoxone test to assess the effects of caffeine on auditory brainstem response.Results: Compared to control group the latencies of waves III,V and I-V interpeak interval of the cases decreased significantly after 2 and 3mg/kg BW caffeine consumption. Wave I latency significantly decreased after 3mg/kg BW caffeine consumption(p<0.01. Conclusion: Increasing of the glutamate level resulted from the adenosine receptor blocking brings about changes in conduction in the central auditory pathway.

  11. The harmonic organization of auditory cortex.

    Science.gov (United States)

    Wang, Xiaoqin

    2013-01-01

    A fundamental structure of sounds encountered in the natural environment is the harmonicity. Harmonicity is an essential component of music found in all cultures. It is also a unique feature of vocal communication sounds such as human speech and animal vocalizations. Harmonics in sounds are produced by a variety of acoustic generators and reflectors in the natural environment, including vocal apparatuses of humans and animal species as well as music instruments of many types. We live in an acoustic world full of harmonicity. Given the widespread existence of the harmonicity in many aspects of the hearing environment, it is natural to expect that it be reflected in the evolution and development of the auditory systems of both humans and animals, in particular the auditory cortex. Recent neuroimaging and neurophysiology experiments have identified regions of non-primary auditory cortex in humans and non-human primates that have selective responses to harmonic pitches. Accumulating evidence has also shown that neurons in many regions of the auditory cortex exhibit characteristic responses to harmonically related frequencies beyond the range of pitch. Together, these findings suggest that a fundamental organizational principle of auditory cortex is based on the harmonicity. Such an organization likely plays an important role in music processing by the brain. It may also form the basis of the preference for particular classes of music and voice sounds. PMID:24381544

  12. Colors, colored overlays, and reading skills

    Directory of Open Access Journals (Sweden)

    Arcangelo eUccula

    2014-07-01

    Full Text Available In this article, we are concerned with the role of colors in reading written texts. It has been argued that colored overlays applied above written texts positively influence both reading fluency and reading speed. These effects would be particularly evident for those individuals affected by the so called Meares-Irlen syndrome, i.e. who experience eyestrain and/or visual distortions – e.g. color, shape or movement illusions – while reading. This condition would interest the 12-14% of the general population and up to the 46% of the dyslexic population. Thus, colored overlays have been largely employed as a remedy for some aspects of the difficulties in reading experienced by dyslexic individuals, as fluency and speed. Despite the wide use of colored overlays, how they exert their effects has not been made clear yet. Also, according to some researchers, the results supporting the efficacy of colored overlays as a tool for helping readers are at least controversial. Furthermore, the very nature of the Meares-Irlen syndrome has been questioned. Here we provide a concise, critical review of the literature.

  13. Color Reproduction with a Smartphone

    Science.gov (United States)

    Thoms, Lars-Jochen; Colicchia, Giuseppe; Girwidz, Raimund

    2013-01-01

    The world is full of colors. Most of the colors we see around us can be created on common digital displays simply by superposing light with three different wavelengths. However, no mixture of colors can produce a fully pure color identical to a spectral color. Using a smartphone, students can investigate the main features of primary color addition…

  14. Incompatibility between the principle of the constancy of the speed of light and the Lorentz contraction in the GPS Experiment

    CERN Document Server

    Sato, M

    2007-01-01

    Incompatibility between the principle of the constancy of the speed of light and the Lorentz contraction in the global positioning system (GPS) is discussed. The GPS works precisely in the earth-centered locally inertial (ECI) coordinate system on the condition that the speed of light c is assumed to be constant regardless of the inertial motion of the GPS satellites and the earth. The inertial system of the earth travels not only in the solar system at the velocity 30 km/s but also in the cosmic microwave background (CMB) at the velocity 700 km/s. The deviation on the car navigation system by the Lorentz contraction of 700 km/s is maximally estimated as 54 m. However, such a large deviation is not observed: that is, the Lorentz contraction is not observed in the gravitational field of the earth. If there is a Lorentz contraction, the GPS cannot work so precisely. The GPS satellites are in the gravitational field of the earth, therefore the system should be interpreted by the theory of general relativity as w...

  15. The effect of background music in auditory health persuasion

    NARCIS (Netherlands)

    Elbert, Sarah; Dijkstra, Arie

    2013-01-01

    In auditory health persuasion, threatening information regarding health is communicated by voice only. One relevant context of auditory persuasion is the addition of background music. There are different mechanisms through which background music might influence persuasion, for example through mood (

  16. Auditory Discrimination Development through Vestibulo-Cochlear Stimulation.

    Science.gov (United States)

    Palmer, Lyelle L.

    1980-01-01

    Three types of vestibular activities (active, adaptive, and passively imposed) to improve auditory discrimination development are described and results of a study using the vestibular stimulation techniques with 20 Ss (average age 9) having abnormal auditory discrimination. (PHR)

  17. Musical experience shapes top-down auditory mechanisms: evidence from masking and auditory attention performance.

    Science.gov (United States)

    Strait, Dana L; Kraus, Nina; Parbery-Clark, Alexandra; Ashley, Richard

    2010-03-01

    A growing body of research suggests that cognitive functions, such as attention and memory, drive perception by tuning sensory mechanisms to relevant acoustic features. Long-term musical experience also modulates lower-level auditory function, although the mechanisms by which this occurs remain uncertain. In order to tease apart the mechanisms that drive perceptual enhancements in musicians, we posed the question: do well-developed cognitive abilities fine-tune auditory perception in a top-down fashion? We administered a standardized battery of perceptual and cognitive tests to adult musicians and non-musicians, including tasks either more or less susceptible to cognitive control (e.g., backward versus simultaneous masking) and more or less dependent on auditory or visual processing (e.g., auditory versus visual attention). Outcomes indicate lower perceptual thresholds in musicians specifically for auditory tasks that relate with cognitive abilities, such as backward masking and auditory attention. These enhancements were observed in the absence of group differences for the simultaneous masking and visual attention tasks. Our results suggest that long-term musical practice strengthens cognitive functions and that these functions benefit auditory skills. Musical training bolsters higher-level mechanisms that, when impaired, relate to language and literacy deficits. Thus, musical training may serve to lessen the impact of these deficits by strengthening the corticofugal system for hearing. PMID:20018234

  18. Cooperative dynamics in auditory brain response

    CERN Document Server

    Kwapien, J; Liu, L C; Ioannides, A A

    1998-01-01

    Simultaneous estimates of the activity in the left and right auditory cortex of five normal human subjects were extracted from Multichannel Magnetoencephalography recordings. Left, right and binaural stimulation were used, in separate runs, for each subject. The resulting time-series of left and right auditory cortex activity were analysed using the concept of mutual information. The analysis constitutes an objective method to address the nature of inter-hemispheric correlations in response to auditory stimulations. The results provide a clear evidence for the occurrence of such correlations mediated by a direct information transport, with clear laterality effects: as a rule, the contralateral hemisphere leads by 10-20ms, as can be seen in the average signal. The strength of the inter-hemispheric coupling, which cannot be extracted from the average data, is found to be highly variable from subject to subject, but remarkably stable for each subject.

  19. Applied research in auditory data representation

    Science.gov (United States)

    Frysinger, Steve P.

    1990-08-01

    A class of data displays, characterized generally as Auditory Data Representation, is described and motivated. This type of data representation takes advantage of the tremendous pattern recognition capability of the human auditory channel. Audible displays offer an alternative means of conveying quantitative data to the analyst to facilitate information extraction, and are successfully used alone and in conjunction with visual displays. The Auditory Data Representation literature is reviewed, along with elements of the allied fields of investigation, Psychoacoustics and Musical Perception. A methodology for applied research in this field, based upon the well-developed discipline of psychophysics, is elaborated using a recent experiment as a case study. This method permits objective estimation of a data representation technique by comparing it to alternative displays for the pattern recognition task at hand. The psychophysical threshold of signal to noise level, for constant pattern recognition performance, is the measure of display effectiveness.

  20. Are auditory percepts determined by experience?

    Science.gov (United States)

    Monson, Brian B; Han, Shui'Er; Purves, Dale

    2013-01-01

    Audition--what listeners hear--is generally studied in terms of the physical properties of sound stimuli and physiological properties of the auditory system. Based on recent work in vision, we here consider an alternative perspective that sensory percepts are based on past experience. In this framework, basic auditory qualities (e.g., loudness and pitch) are based on the frequency of occurrence of stimulus patterns in natural acoustic stimuli. To explore this concept of audition, we examined five well-documented psychophysical functions. The frequency of occurrence of acoustic patterns in a database of natural sound stimuli (speech) predicts some qualitative aspects of these functions, but with substantial quantitative discrepancies. This approach may offer a rationale for auditory phenomena that are difficult to explain in terms of the physical attributes of the stimuli as such.

  1. Are auditory percepts determined by experience?

    Directory of Open Access Journals (Sweden)

    Brian B Monson

    Full Text Available Audition--what listeners hear--is generally studied in terms of the physical properties of sound stimuli and physiological properties of the auditory system. Based on recent work in vision, we here consider an alternative perspective that sensory percepts are based on past experience. In this framework, basic auditory qualities (e.g., loudness and pitch are based on the frequency of occurrence of stimulus patterns in natural acoustic stimuli. To explore this concept of audition, we examined five well-documented psychophysical functions. The frequency of occurrence of acoustic patterns in a database of natural sound stimuli (speech predicts some qualitative aspects of these functions, but with substantial quantitative discrepancies. This approach may offer a rationale for auditory phenomena that are difficult to explain in terms of the physical attributes of the stimuli as such.

  2. Phonetic categorization in auditory word perception.

    Science.gov (United States)

    Ganong, W F

    1980-02-01

    To investigate the interaction in speech perception of auditory information and lexical knowledge (in particular, knowledge of which phonetic sequences are words), acoustic continua varying in voice onset time were constructed so that for each acoustic continuum, one of the two possible phonetic categorizations made a word and the other did not. For example, one continuum ranged between the word dash and the nonword tash; another used the nonword dask and the word task. In two experiments, subjects showed a significant lexical effect--that is, a tendency to make phonetic categorizations that make words. This lexical effect was greater at the phoneme boundary (where auditory information is ambiguous) than at the ends of the condinua. Hence the lexical effect must arise at a stage of processing sensitive to both lexical knowledge and auditory information.

  3. Auditory temporal processes in the elderly

    Directory of Open Access Journals (Sweden)

    E. Ben-Artzi

    2011-03-01

    Full Text Available Several studies have reported age-related decline in auditory temporal resolution and in working memory. However, earlier studies did not provide evidence as to whether these declines reflect overall changes in the same mechanisms, or reflect age-related changes in two independent mechanisms. In the current study we examined whether the age-related decline in auditory temporal resolution and in working memory would remain significant even after controlling for their shared variance. Eighty-two participants, aged 21-82 performed the dichotic temporal order judgment task and the backward digit span task. The findings indicate that age-related decline in auditory temporal resolution and in working memory are two independent processes.

  4. Affective Image Colorization

    Institute of Scientific and Technical Information of China (English)

    Xiao-Hui Wang; Jia Jia; Han-Yu Liao; Lian-Hong Cai

    2012-01-01

    Colorization of gray-scale images has attracted many attentions for a long time.An important role of image color is the conveyer of emotions (through color themes).The colorization with an undesired color theme is less useful,even it is semantically correct.However this has been rarely considered.Automatic colorization respecting both the semantics and the emotions is undoubtedly a challenge.In this paper,we propose a complete system for affective image colorization.We only need the user to assist object segmentation along with text labels and an affective word.First,the text labels along with other object characters are jointly used to filter the internet images to give each object a set of semantically correct reference images.Second,we select a set of color themes according to the affective word based on art theories.With these themes,a generic algorithm is used to select the best reference for each object,balancing various requirements.Finally,we propose a hybrid texture synthesis approach for colorization.To the best of our knowledge,it is the first system which is able to efficiently colorize a gray-scale image semantically by an emotionally controllable fashion.Our experiments show the effectiveness of our system,especially the benefit compared with the previous Markov random field (MRF) based method.

  5. What determines auditory distraction? On the roles of local auditory changes and expectation violations.

    Directory of Open Access Journals (Sweden)

    Jan P Röer

    Full Text Available Both the acoustic variability of a distractor sequence and the degree to which it violates expectations are important determinants of auditory distraction. In four experiments we examined the relative contribution of local auditory changes on the one hand and expectation violations on the other hand in the disruption of serial recall by irrelevant sound. We present evidence for a greater disruption by auditory sequences ending in unexpected steady state distractor repetitions compared to auditory sequences with expected changing state endings even though the former contained fewer local changes. This effect was demonstrated with piano melodies (Experiment 1 and speech distractors (Experiment 2. Furthermore, it was replicated when the expectation violation occurred after the encoding of the target items (Experiment 3, indicating that the items' maintenance in short-term memory was disrupted by attentional capture and not their encoding. This seems to be primarily due to the violation of a model of the specific auditory distractor sequences because the effect vanishes and even reverses when the experiment provides no opportunity to build up a specific neural model about the distractor sequence (Experiment 4. Nevertheless, the violation of abstract long-term knowledge about auditory regularities seems to cause a small and transient capture effect: Disruption decreased markedly over the course of the experiments indicating that participants habituated to the unexpected distractor repetitions across trials. The overall pattern of results adds to the growing literature that the degree to which auditory distractors violate situation-specific expectations is a more important determinant of auditory distraction than the degree to which a distractor sequence contains local auditory changes.

  6. Auditory Neuropathy Spectrum Disorder Masquerading as Social Anxiety

    OpenAIRE

    Behere, Rishikesh V.; Rao, Mukund G.; Mishra, Shree; Varambally, Shivarama; Nagarajarao, Shivashankar; Bangalore N Gangadhar

    2015-01-01

    The authors report a case of a 47-year-old man who presented with treatment-resistant anxiety disorder. Behavioral observation raised clinical suspicion of auditory neuropathy spectrum disorder. The presence of auditory neuropathy spectrum disorder was confirmed on audiological investigations. The patient was experiencing extreme symptoms of anxiety, which initially masked the underlying diagnosis of auditory neuropathy spectrum disorder. Challenges in diagnosis and treatment of auditory neur...

  7. ABR and auditory P300 findings inchildren with ADHD

    OpenAIRE

    Schochat Eliane; Scheuer Claudia Ines; Andrade Ênio Roberto de

    2002-01-01

    Auditory processing disorders (APD), also referred as central auditory processing disorders (CAPD) and attention deficit hyperactivity disorders (ADHD) have become popular diagnostic entities for school age children. It has been demonstrated a high incidence of comorbid ADHD with communication disorders and auditory processing disorder. The aim of this study was to investigate ABR and P300 auditory evoked potentials in children with ADHD, in a double-blind study. Twenty-one children, ages bet...

  8. Functional neuroanatomy of auditory scene analysis in Alzheimer's disease

    OpenAIRE

    Golden, Hannah L.; Jennifer L. Agustus; Johanna C. Goll; Downey, Laura E; Mummery, Catherine J.; Jonathan M Schott; Crutch, Sebastian J.; Jason D Warren

    2015-01-01

    Auditory scene analysis is a demanding computational process that is performed automatically and efficiently by the healthy brain but vulnerable to the neurodegenerative pathology of Alzheimer's disease. Here we assessed the functional neuroanatomy of auditory scene analysis in Alzheimer's disease using the well-known ‘cocktail party effect’ as a model paradigm whereby stored templates for auditory objects (e.g., hearing one's spoken name) are used to segregate auditory ‘foreground’ and ‘back...

  9. Auditory and motor imagery modulate learning in music performance

    Directory of Open Access Journals (Sweden)

    Rachel M. Brown

    2013-07-01

    Full Text Available Skilled performers such as athletes or musicians can improve their performance by imagining the actions or sensory outcomes associated with their skill. Performers vary widely in their auditory and motor imagery abilities, and these individual differences influence sensorimotor learning. It is unknown whether imagery abilities influence both memory encoding and retrieval. We examined how auditory and motor imagery abilities influence musicians’ encoding (during Learning, as they practiced novel melodies, and retrieval (during Recall of those melodies. Pianists learned melodies by listening without performing (auditory learning or performing without sound (motor learning; following Learning, pianists performed the melodies from memory with auditory feedback (Recall. During either Learning (Experiment 1 or Recall (Experiment 2, pianists experienced either auditory interference, motor interference, or no interference. Pitch accuracy (percentage of correct pitches produced and temporal regularity (variability of quarter-note interonset intervals were measured at Recall. Independent tests measured auditory and motor imagery skills. Pianists’ pitch accuracy was higher following auditory learning than following motor learning and lower in motor interference conditions (Experiments 1 and 2. Both auditory and motor imagery skills improved pitch accuracy overall. Auditory imagery skills modulated pitch accuracy encoding (Experiment 1: Higher auditory imagery skill corresponded to higher pitch accuracy following auditory learning with auditory or motor interference, and following motor learning with motor or no interference. These findings suggest that auditory imagery abilities decrease vulnerability to interference and compensate for missing auditory feedback at encoding. Auditory imagery skills also influenced temporal regularity at retrieval (Experiment 2: Higher auditory imagery skill predicted greater temporal regularity during Recall in the

  10. Auditory Brainstem Response Improvements in Hyperbillirubinemic Infants

    Science.gov (United States)

    Abdollahi, Farzaneh Zamiri; Manchaiah, Vinaya; Lotfi, Yones

    2016-01-01

    Background and Objectives Hyperbillirubinemia in infants have been associated with neuronal damage including in the auditory system. Some researchers have suggested that the bilirubin-induced auditory neuronal damages may be temporary and reversible. This study was aimed at investigating the auditory neuropathy and reversibility of auditory abnormalities in hyperbillirubinemic infants. Subjects and Methods The study participants included 41 full term hyperbilirubinemic infants (mean age 39.24 days) with normal birth weight (3,200-3,700 grams) that admitted in hospital for hyperbillirubinemia and 39 normal infants (mean age 35.54 days) without any hyperbillirubinemia or other hearing loss risk factors for ruling out maturational changes. All infants in hyperbilirubinemic group had serum bilirubin level more than 20 milligram per deciliter and undergone one blood exchange transfusion. Hearing evaluation for each infant was conducted twice: the first one after hyperbilirubinemia treatment and before leaving hospital and the second one three months after the first hearing evaluation. Hearing evaluations included transient evoked otoacoustic emission (TEOAE) screening and auditory brainstem response (ABR) threshold tracing. Results The TEOAE and ABR results of control group and TEOAE results of the hyperbilirubinemic group did not change significantly from the first to the second evaluation. However, the ABR results of the hyperbilirubinemic group improved significantly from the first to the second assessment (p=0.025). Conclusions The results suggest that the bilirubin induced auditory neuronal damage can be reversible over time so we suggest that infants with hyperbilirubinemia who fail the first hearing tests should be reevaluated after 3 months of treatment. PMID:27144228

  11. Color improves ‘visual’ acuity via sound

    Directory of Open Access Journals (Sweden)

    Shelly eLevy-Tzedek

    2014-11-01

    Full Text Available Visual-to-auditory sensory substitution devices (SSDs convey visual information via sound, with the primary goal of making visual information accessible to blind and visually impaired individuals. We developed the EyeMusic SSD, which transforms shape, location and color information into musical notes. We tested the 'visual' acuity of 23 individuals (13 blind and 10 blindfolded sighted on the Snellen tumbling-E test, with the EyeMusic. Participants were asked to determine the orientation of the letter ‘E’. The test was repeated twice: in one test, the letter ‘E’ was drawn with a single color (white, and in the other test, with two colors (red and white. In the latter case, the vertical line in the letter, when upright, was drawn in red, with the three horizontal lines drawn in white. We found no significant differences in performance between the blind and the sighted groups. We found a significant effect of the added color on the ‘visual’ acuity. The highest acuity participants reached in the monochromatic test was 20/800, whereas with the added color, acuity doubled to 20/400. We conclude that color improves 'visual' acuity via sound.

  12. A virtual auditory environment for investigating the auditory signal processing of realistic sounds

    DEFF Research Database (Denmark)

    Favrot, Sylvain Emmanuel

    A loudspeaker-based virtual auditory environment (VAE) has been developed to provide a realistic versatile research environment for investigating the auditory signal processing in real environments, i.e., considering multiple sound sources and room reverberation. The VAE allows a full control of...... the acoustic scenario in order to systematically study the auditory processing of reverberant sounds. It is based on the ODEON software, which is state-of-the-art software for room acoustic simulations developed at Acoustic Technology, DTU. First, a MATLAB interface to the ODEON software has been...

  13. Transient auditory hallucinations in an adolescent.

    Science.gov (United States)

    Skokauskas, Norbert; Pillay, Devina; Moran, Tom; Kahn, David A

    2010-05-01

    In adolescents, hallucinations can be a transient illness or can be associated with non-psychotic psychopathology, psychosocial adversity, or a physical illness. We present the case of a 15-year-old secondary-school student who presented with a 1-month history of first onset auditory hallucinations, which had been increasing in frequency and severity, and mild paranoid ideation. Over a 10-week period, there was a gradual diminution, followed by a complete resolution, of symptoms. We discuss issues regarding the diagnosis and prognosis of auditory hallucinations in adolescents.

  14. Do dyslexics have auditory input processing difficulties?

    DEFF Research Database (Denmark)

    Poulsen, Mads

    2011-01-01

    Word production difficulties are well documented in dyslexia, whereas the results are mixed for receptive phonological processing. This asymmetry raises the possibility that the core phonological deficit of dyslexia is restricted to output processing stages. The present study investigated whether...... a group of dyslexics had word level receptive difficulties using an auditory lexical decision task with long words and nonsense words. The dyslexics were slower and less accurate than chronological age controls in an auditory lexical decision task, with disproportionate low performance on nonsense words...

  15. Subsymmetries predict auditory and visual pattern complexity.

    Science.gov (United States)

    Toussaint, Godfried T; Beltran, Juan F

    2013-01-01

    A mathematical measure of pattern complexity based on subsymmetries possessed by the pattern, previously shown to correlate highly with empirically derived measures of cognitive complexity in the visual domain, is found to also correlate significantly with empirically derived complexity measures of perception and production of auditory temporal and musical rhythmic patterns. Not only does the subsymmetry measure correlate highly with the difficulty of reproducing the rhythms by tapping after listening to them, but also the empirical measures exhibit similar behavior, for both the visual and auditory patterns, as a function of the relative number of subsymmetries present in the patterns. PMID:24494441

  16. Enhancing Color Representation for the Color Vision Impaired

    OpenAIRE

    Huang, Jia-Bin; Wu, Sih-Ying; Chen, Chu-Song

    2008-01-01

    In this paper, we propose a fast re-coloring algorithm to improve the accessibility for the color vision impaired. Compared to people with normal color vision, people with color vision impairment have difficulty in distinguishing between certain combinations of colors. This may hinder visual communication owing to the increasing use of colors in recent years. To address this problem, we re-map the hue components in the HSV color space based on the statistics of local characteristics of the or...

  17. AN EVALUATION OF AUDITORY LEARNING IN FILIAL IMPRINTING

    NARCIS (Netherlands)

    BOLHUIS, JJ; VANKAMPEN, HS

    1992-01-01

    The characteristics of auditory learning in filial imprinting in precocial birds are reviewed. Numerous studies have demonstrated that the addition of an auditory stimulus improves following of a visual stimulus. This paper evaluates whether there is genuine auditory imprinting, i.e. the formation o

  18. Color image segmentation

    Science.gov (United States)

    McCrae, Kimberley A.; Ruck, Dennis W.; Rogers, Steven K.; Oxley, Mark E.

    1994-03-01

    The most difficult stage of automated target recognition is segmentation. Current segmentation problems include faces and tactical targets; previous efforts to segment these objects have used intensity and motion cues. This paper develops a color preprocessing scheme to be used with the other segmentation techniques. A neural network is trained to identify the color of a desired object, eliminating all but that color from the scene. Gabor correlations and 2D wavelet transformations will be performed on stationary images; and 3D wavelet transforms on multispectral data will incorporate color and motion detection into the machine visual system. The paper will demonstrate that color and motion cues can enhance a computer segmentation system. Results from segmenting faces both from the AFIT data base and from video taped television are presented; results from tactical targets such as tanks and airplanes are also given. Color preprocessing is shown to greatly improve the segmentation in most cases.

  19. The road coloring problem

    CERN Document Server

    Trahtman, A N

    2007-01-01

    The synchronizing word of deterministic automaton is a word in the alphabet of colors (considered as letters) of its edges that maps the automaton to a single state. A coloring of edges of a directed graph is synchronizing if the coloring turns the graph into deterministic finite automaton possessing a synchronizing word. The road coloring problem is a problem of synchronizing coloring of directed finite strongly connected graph with constant outdegree of all its vertices if the greatest common divisor of lengths of all its cycles is one. The problem was posed by Adler, Goodwyn and Weiss over 30 years ago and evoked a noticeable interest among the specialists in theory of graphs, deterministic automata and symbolic dynamics. The problem is described even in "Vikipedia" - the popular Internet Encyclopedia. The positive solution of the road coloring problem is presented.

  20. Masters Colors -meikkisarjan lanseeraus

    OpenAIRE

    Muhonen, Veera; Renlund, Siri

    2013-01-01

    Toiminnallisen opinnäytetyön tarkoituksena oli suunnitella ja toteuttaa Masters Colors –meikkisarjan lanseeraustoimenpiteet. Opinnäytetyö toteutettiin yhteistyössä hoitolakosmetiikan maahantuontiyritys Benecom Oy:n kanssa. Yrityksen päätoimisena maahantuontisarjana toimii Guinot-hoitolakosmetiikkasarja, jonka lisäksi Benecom Oy tuo maahan Guinot-konsernin Masters Colors –meikkisarjaa sekä Cosmecology –kosmetiikkaa. Masters Colors on kehitetty laajentamaan Guinot-kauneushoitoloiden palveluvali...

  1. The Translation Of Colors

    Institute of Scientific and Technical Information of China (English)

    王冰

    2012-01-01

    Different nations have different or even opposite perception of color, which results in non-equivalence of color words in mutual translation between Chinese and English. This paper is to discuss non-equivalence of color words between Chinese and English on the two aspects and emphasizes the importance of transmitting cultural message accurately in the mutual translation between Chinese and English. Studying the cultural connotations of the words is of great importance for successful communication.

  2. Color mixing models

    Science.gov (United States)

    Harrington, Steven J.

    1992-05-01

    In black-and-white printing the page image can be represented within a computer as an array of binary values indicating whether or not pixels should be inked. The Boolean operators of AND, OR, and EXCLUSIVE-OR are often used when adding new objects to the image array. For color printing the page may be represented as an array of continuous tone color values, and the generalization of these logic functions to gray-scale or full-color images is, in general, not defined or understood. When incrementally composing a page image new colors can replace old in an image buffer, or new colors and old can be combined according to some mixing function to form a composite color which is stored. This paper examines the properties of the Boolean operations and suggests full-color mixing functions which preserve the desired properties. These functions can be used to combine colored images, giving various transparency effects. The relationships between the mixing functions and physical models of color mixing are also discussed.

  3. How color effekts communication

    OpenAIRE

    Sachilovich, K. P.

    2013-01-01

    When speaking about communication, there are, in fact two aspects that come into mind, namely, verbal and non-verbal communication. By nonverbal means of communication people usually mean mimics, gestures, posture, voice, intonation, etc. But very few of them are aware of the fact that color is also a means of non-verbal communication, and a very powerful one. When talking about color I mean color in every meaning of the word. For instance, let’s take the color of walls in classrooms or a...

  4. Polarization encoded color camera.

    Science.gov (United States)

    Schonbrun, Ethan; Möller, Guðfríður; Di Caprio, Giuseppe

    2014-03-15

    Digital cameras would be colorblind if they did not have pixelated color filters integrated into their image sensors. Integration of conventional fixed filters, however, comes at the expense of an inability to modify the camera's spectral properties. Instead, we demonstrate a micropolarizer-based camera that can reconfigure its spectral response. Color is encoded into a linear polarization state by a chiral dispersive element and then read out in a single exposure. The polarization encoded color camera is capable of capturing three-color images at wavelengths spanning the visible to the near infrared. PMID:24690806

  5. Ecrire et souffrir : L’inspiration partagée de Constance Fenimore Woolson et de Henry James Literature and Grief: Constance Fenimore Woolson and Henry James, A Common Inspiration

    Directory of Open Access Journals (Sweden)

    Jeannine Hayat

    2007-01-01

    Full Text Available Miss Grief is a story by Constance Fenimore Woolson, an American novelist who often wrote about the difficulty a woman had in becoming an artist — a writer or a painter — in the nineteenth century. This tale is a very strange text, a kind of anticipation of a meeting to come, in Italy, in 1880, between Woolson and Henry James, and a friendship which lasted until the former’s death in 1894. For thirteen years, both writers would share a common inspiration. Death itself could not break the links between the two authors, who were connected even when settled in different European countries. William James, who was a member of the American Society for Psychical Research, probably helped his brother Henry to communicate — or so it appears — in some way with Woolson, even after her fatal accident, or possible suicide, in Venice. Henry James probably had in mind Miss Grief, a story by his dead friend, before writing some of his books. Indeed, Woolson had been the first to develop the image of “the figure in the carpet,” which was later transformed by Henry James. Woolson was also the first to devise a plot which Henry James would later use as a canvas for his novel The Wings of the Dove. What is an author and what is authorship? It seems impossible to separate what is Woolson’s and what is Henry James’s in four works of fiction that are in fact to be read together : Miss Grief, The Figure in the Carpet, The Beast in the Jungle, The Wings of the Dove.

  6. Omni-Lie Color Algebras and Lie Color 2-Algebras

    OpenAIRE

    Zhang, Tao

    2013-01-01

    Omni-Lie color algebras over an abelian group with a bicharacter are studied. The notions of 2-term color $L_{\\infty}$-algebras and Lie color 2-algebras are introduced. It is proved that there is a one-to-one correspondence between Lie color 2-algebras and 2-term color $L_{\\infty}$-algebras.

  7. Encyclopedia of color science and technology

    CERN Document Server

    2016-01-01

    The Encyclopedia of Color Science and Technology provides an authoritative single source for understanding and applying the concepts of color to all fields of science and technology, including artistic and historical aspects of color. Many topics are discussed in this timely reference, including an introduction to the science of color, and entries on the physics, chemistry and perception of color. Color is described as it relates to optical phenomena of color and continues on through colorants and materials used to modulate color and also to human vision of color. The measurement of color is provided as is colorimetry, color spaces, color difference metrics, color appearance models, color order systems and cognitive color. Other topics discussed include industrial color, color imaging, capturing color, displaying color and printing color. Descriptions of color encodings, color management, processing color and applications relating to color synthesis for computer graphics are included in this work. The Encyclo...

  8. Navigation lights color study

    Science.gov (United States)

    Barbosa, Jose G.; Alberg, Matthew T.

    2015-05-01

    The chromaticity of navigation lights are defined by areas on the International Commission on Illumination (CIE) 1931 chromaticity diagram. The corner coordinates for these areas are specified in the International Regulations for Prevention of Collisions at Sea, 1972 (72 COLREGS). The navigation light's color of white, red, green, and yellow are bounded by these areas. The chromaticity values specified by the COLREGS for navigation lights were intended for the human visual system (HVS). The HVS can determine the colors of these lights easily under various conditions. For digital color camera imaging systems the colors of these lights are dependent on the camera's color spectral sensitivity, settings, and color correction. At night the color of these lights are used to quickly determine the relative course of vessels. If these lights are incorrectly identified or there is a delay in identifying them this could be a potential safety of ship concern. Vessels that use camera imaging systems exclusively for sight, at night, need to detect, identify, and discriminate navigation lights for navigation and collision avoidance. The introduction of light emitting diode (LED) lights and lights with different spectral signatures have the potential to be imaged very differently with an RGB color filter array (CFA) color camera than with the human eye. It has been found that some green navigation lights' images appear blue verse green. This has an impact on vessels that use camera imaging systems exclusively for navigation. This paper will characterize color cameras ability to properly reproducing navigation lights' color and survey a set of navigation light to determine if they conform to the COLREGS.

  9. The Goldilocks Effect in Infant Auditory Attention

    Science.gov (United States)

    Kidd, Celeste; Piantadosi, Steven T.; Aslin, Richard N.

    2014-01-01

    Infants must learn about many cognitive domains (e.g., language, music) from auditory statistics, yet capacity limits on their cognitive resources restrict the quantity that they can encode. Previous research has established that infants can attend to only a subset of available acoustic input. Yet few previous studies have directly examined infant…

  10. Reading adn Auditory-Visual Equivalences

    Science.gov (United States)

    Sidman, Murray

    1971-01-01

    A retarded boy, unable to read orally or with comprehension, was taught to match spoken to printed words and was then capable of reading comprehension (matching printed words to picture) and oral reading (naming printed words aloud), demonstrating that certain learned auditory-visual equivalences are sufficient prerequisites for reading…

  11. Development of Receiver Stimulator for Auditory Prosthesis

    Directory of Open Access Journals (Sweden)

    K. Raja Kumar

    2010-05-01

    Full Text Available The Auditory Prosthesis (AP is an electronic device that can provide hearing sensations to people who are profoundly deaf by stimulating the auditory nerve via an array of electrodes with an electric current allowing them to understand the speech. The AP system consists of two hardware functional units such as Body Worn Speech Processor (BWSP and Receiver Stimulator. The prototype model of Receiver Stimulator for Auditory Prosthesis (RSAP consists of Speech Data Decoder, DAC, ADC, constant current generator, electrode selection logic, switch matrix and simulated electrode resistance array. The laboratory model of speech processor is designed to implement the Continuous Interleaved Sampling (CIS speech processing algorithm which generates the information required for electrode stimulation based on the speech / audio data. Speech Data Decoder receives the encoded speech data via an inductive RF transcutaneous link from speech processor. Twelve channels of auditory Prosthesis with selectable eight electrodes for stimulation of simulated electrode resistance array are used for testing. The RSAP is validated by using the test data generated by the laboratory prototype of speech processor. The experimental results are obtained from specific speech/sound tests using a high-speed data acquisition system and found satisfactory.

  12. Auditory Training with Frequent Communication Partners

    Science.gov (United States)

    Tye-Murray, Nancy; Spehar, Brent; Sommers, Mitchell; Barcroft, Joe

    2016-01-01

    Purpose: Individuals with hearing loss engage in auditory training to improve their speech recognition. They typically practice listening to utterances spoken by unfamiliar talkers but never to utterances spoken by their most frequent communication partner (FCP)--speech they most likely desire to recognize--under the assumption that familiarity…

  13. Auditory Perception of Statistically Blurred Sound Textures

    DEFF Research Database (Denmark)

    McWalter, Richard Ian; MacDonald, Ewen; Dau, Torsten

    Sound textures have been identified as a category of sounds which are processed by the peripheral auditory system and captured with running timeaveraged statistics. Although sound textures are temporally homogeneous, they offer a listener with enough information to identify and differentiate sour...

  14. Auditory confrontation naming in Alzheimer's disease.

    Science.gov (United States)

    Brandt, Jason; Bakker, Arnold; Maroof, David Aaron

    2010-11-01

    Naming is a fundamental aspect of language and is virtually always assessed with visual confrontation tests. Tests of the ability to name objects by their characteristic sounds would be particularly useful in the assessment of visually impaired patients, and may be particularly sensitive in Alzheimer's disease (AD). We developed an auditory naming task, requiring the identification of the source of environmental sounds (i.e., animal calls, musical instruments, vehicles) and multiple-choice recognition of those not identified. In two separate studies mild-to-moderate AD patients performed more poorly than cognitively normal elderly on the auditory naming task. This task was also more difficult than two versions of a comparable visual naming task, and correlated more highly with Mini-Mental State Exam score. Internal consistency reliability was acceptable, although ROC analysis revealed auditory naming to be slightly less successful than visual confrontation naming in discriminating AD patients from normal participants. Nonetheless, our auditory naming task may prove useful in research and clinical practice, especially with visually impaired patients. PMID:20981630

  15. Lateralization of auditory-cortex functions.

    Science.gov (United States)

    Tervaniemi, Mari; Hugdahl, Kenneth

    2003-12-01

    In the present review, we summarize the most recent findings and current views about the structural and functional basis of human brain lateralization in the auditory modality. Main emphasis is given to hemodynamic and electromagnetic data of healthy adult participants with regard to music- vs. speech-sound encoding. Moreover, a selective set of behavioral dichotic-listening (DL) results and clinical findings (e.g., schizophrenia, dyslexia) are included. It is shown that human brain has a strong predisposition to process speech sounds in the left and music sounds in the right auditory cortex in the temporal lobe. Up to great extent, an auditory area located at the posterior end of the temporal lobe (called planum temporale [PT]) underlies this functional asymmetry. However, the predisposition is not bound to informational sound content but to rapid temporal information more common in speech than in music sounds. Finally, we obtain evidence for the vulnerability of the functional specialization of sound processing. These altered forms of lateralization may be caused by top-down and bottom-up effects inter- and intraindividually In other words, relatively small changes in acoustic sound features or in their familiarity may modify the degree in which the left vs. right auditory areas contribute to sound encoding. PMID:14629926

  16. Self-affirmation in auditory persuasion

    NARCIS (Netherlands)

    Elbert, Sarah; Dijkstra, Arie

    2011-01-01

    Persuasive health information can be presented through an auditory channel. Curiously enough, the effect of voice cues in health persuasion has hardly been studied. Research concerning visual persuasive messages showed that self-affirmation results in a more open-minded reaction to threatening infor

  17. Affective priming with auditory speech stimuli

    NARCIS (Netherlands)

    J. Degner

    2011-01-01

    Four experiments explored the applicability of auditory stimulus presentation in affective priming tasks. In Experiment 1, it was found that standard affective priming effects occur when prime and target words are presented simultaneously via headphones similar to a dichotic listening procedure. In

  18. Integration and segregation in auditory scene analysis

    Science.gov (United States)

    Sussman, Elyse S.

    2005-03-01

    Assessment of the neural correlates of auditory scene analysis, using an index of sound change detection that does not require the listener to attend to the sounds [a component of event-related brain potentials called the mismatch negativity (MMN)], has previously demonstrated that segregation processes can occur without attention focused on the sounds and that within-stream contextual factors influence how sound elements are integrated and represented in auditory memory. The current study investigated the relationship between the segregation and integration processes when they were called upon to function together. The pattern of MMN results showed that the integration of sound elements within a sound stream occurred after the segregation of sounds into independent streams and, further, that the individual streams were subject to contextual effects. These results are consistent with a view of auditory processing that suggests that the auditory scene is rapidly organized into distinct streams and the integration of sequential elements to perceptual units takes place on the already formed streams. This would allow for the flexibility required to identify changing within-stream sound patterns, needed to appreciate music or comprehend speech..

  19. Auditory risk estimates for youth target shooting

    Science.gov (United States)

    Meinke, Deanna K.; Murphy, William J.; Finan, Donald S.; Lankford, James E.; Flamme, Gregory A.; Stewart, Michael; Soendergaard, Jacob; Jerome, Trevor W.

    2015-01-01

    Objective To characterize the impulse noise exposure and auditory risk for youth recreational firearm users engaged in outdoor target shooting events. The youth shooting positions are typically standing or sitting at a table, which places the firearm closer to the ground or reflective surface when compared to adult shooters. Design Acoustic characteristics were examined and the auditory risk estimates were evaluated using contemporary damage-risk criteria for unprotected adult listeners and the 120-dB peak limit suggested by the World Health Organization (1999) for children. Study sample Impulses were generated by 26 firearm/ammunition configurations representing rifles, shotguns, and pistols used by youth. Measurements were obtained relative to a youth shooter’s left ear. Results All firearms generated peak levels that exceeded the 120 dB peak limit suggested by the WHO for children. In general, shooting from the seated position over a tabletop increases the peak levels, LAeq8 and reduces the unprotected maximum permissible exposures (MPEs) for both rifles and pistols. Pistols pose the greatest auditory risk when fired over a tabletop. Conclusion Youth should utilize smaller caliber weapons, preferably from the standing position, and always wear hearing protection whenever engaging in shooting activities to reduce the risk for auditory damage. PMID:24564688

  20. Interhemispheric Auditory Connectivity: Structure and Function Related to Auditory Verbal Hallucinations

    Directory of Open Access Journals (Sweden)

    Saskia eSteinmann

    2014-02-01

    Full Text Available Auditory verbal hallucinations (AVH are one of the most common and most distressing symptoms of schizophrenia. Despite fundamental research, the underlying neurocognitive and neurobiological mechanisms are still a matter of debate. Previous studies suggested that hearing voices is associated with a number of factors including local deficits in the left auditory cortex and a disturbed connectivity of frontal and temporoparietal language-related areas. In addition, it is hypothesized that the interhemispheric pathways connecting right and left auditory cortices might be involved in the pathogenesis of AVH. Findings based on Diffusion-Tensor-Imaging (DTI measurements revealed a remarkable interindividual variability in size and shape of the interhemispheric auditory pathways. Interestingly, schizophrenia patients suffering from AVH exhibited increased fractional anisotropy (FA in the interhemispheric fibers than non-hallucinating patients. Thus, higher FA-values indicate an increased severity of AVH. Moreover, a dichotic listening (DL task showed that the interindividual variability in the interhemispheric auditory pathways was reflected in the behavioral outcome: Stronger pathways supported a better information transfer and consequently improved speech perception. This detection indicates a specific structure-function relationship, which seems to be interindividually variable. This review focuses on recent findings concerning the structure-function relationship of the interhemispheric pathways in controls, hallucinating and non-hallucinating schizophrenia patients and concludes that changes in the structural and functional connectivity of auditory areas are involved in the pathophysiology of AVH.

  1. Biological impact of auditory expertise across the life span: musicians as a model of auditory learning.

    Science.gov (United States)

    Strait, Dana L; Kraus, Nina

    2014-02-01

    Experience-dependent characteristics of auditory function, especially with regard to speech-evoked auditory neurophysiology, have garnered increasing attention in recent years. This interest stems from both pragmatic and theoretical concerns as it bears implications for the prevention and remediation of language-based learning impairment in addition to providing insight into mechanisms engendering experience-dependent changes in human sensory function. Musicians provide an attractive model for studying the experience-dependency of auditory processing in humans due to their distinctive neural enhancements compared to nonmusicians. We have only recently begun to address whether these enhancements are observable early in life, during the initial years of music training when the auditory system is under rapid development, as well as later in life, after the onset of the aging process. Here we review neural enhancements in musically trained individuals across the life span in the context of cellular mechanisms that underlie learning, identified in animal models. Musicians' subcortical physiologic enhancements are interpreted according to a cognitive framework for auditory learning, providing a model in which to study mechanisms of experience-dependent changes in human auditory function. PMID:23988583

  2. 40 Hz auditory steady state response to linguistic features of stimuli during auditory hallucinations.

    Science.gov (United States)

    Ying, Jun; Yan, Zheng; Gao, Xiao-rong

    2013-10-01

    The auditory steady state response (ASSR) may reflect activity from different regions of the brain, depending on the modulation frequency used. In general, responses induced by low rates (≤40 Hz) emanate mostly from central structures of the brain, and responses from high rates (≥80 Hz) emanate mostly from the peripheral auditory nerve or brainstem structures. Besides, it was reported that the gamma band ASSR (30-90 Hz) played an important role in working memory, speech understanding and recognition. This paper investigated the 40 Hz ASSR evoked by modulated speech and reversed speech. The speech was Chinese phrase voice, and the noise-like reversed speech was obtained by temporally reversing the speech. Both auditory stimuli were modulated with a frequency of 40 Hz. Ten healthy subjects and 5 patients with hallucination symptom participated in the experiment. Results showed reduction in left auditory cortex response when healthy subjects listened to the reversed speech compared with the speech. In contrast, when the patients who experienced auditory hallucinations listened to the reversed speech, the auditory cortex of left hemispheric responded more actively. The ASSR results were consistent with the behavior results of patients. Therefore, the gamma band ASSR is expected to be helpful for rapid and objective diagnosis of hallucination in clinic. PMID:24142731

  3. Biological impact of auditory expertise across the life span: musicians as a model of auditory learning.

    Science.gov (United States)

    Strait, Dana L; Kraus, Nina

    2014-02-01

    Experience-dependent characteristics of auditory function, especially with regard to speech-evoked auditory neurophysiology, have garnered increasing attention in recent years. This interest stems from both pragmatic and theoretical concerns as it bears implications for the prevention and remediation of language-based learning impairment in addition to providing insight into mechanisms engendering experience-dependent changes in human sensory function. Musicians provide an attractive model for studying the experience-dependency of auditory processing in humans due to their distinctive neural enhancements compared to nonmusicians. We have only recently begun to address whether these enhancements are observable early in life, during the initial years of music training when the auditory system is under rapid development, as well as later in life, after the onset of the aging process. Here we review neural enhancements in musically trained individuals across the life span in the context of cellular mechanisms that underlie learning, identified in animal models. Musicians' subcortical physiologic enhancements are interpreted according to a cognitive framework for auditory learning, providing a model in which to study mechanisms of experience-dependent changes in human auditory function.

  4. McGurk illusion recalibrates subsequent auditory perception.

    Science.gov (United States)

    Lüttke, Claudia S; Ekman, Matthias; van Gerven, Marcel A J; de Lange, Floris P

    2016-01-01

    Visual information can alter auditory perception. This is clearly illustrated by the well-known McGurk illusion, where an auditory/aba/ and a visual /aga/ are merged to the percept of 'ada'. It is less clear however whether such a change in perception may recalibrate subsequent perception. Here we asked whether the altered auditory perception due to the McGurk illusion affects subsequent auditory perception, i.e. whether this process of fusion may cause a recalibration of the auditory boundaries between phonemes. Participants categorized auditory and audiovisual speech stimuli as /aba/, /ada/ or /aga/ while activity patterns in their auditory cortices were recorded using fMRI. Interestingly, following a McGurk illusion, an auditory /aba/ was more often misperceived as 'ada'. Furthermore, we observed a neural counterpart of this recalibration in the early auditory cortex. When the auditory input /aba/ was perceived as 'ada', activity patterns bore stronger resemblance to activity patterns elicited by /ada/ sounds than when they were correctly perceived as /aba/. Our results suggest that upon experiencing the McGurk illusion, the brain shifts the neural representation of an /aba/ sound towards /ada/, culminating in a recalibration in perception of subsequent auditory input. PMID:27611960

  5. McGurk illusion recalibrates subsequent auditory perception

    Science.gov (United States)

    Lüttke, Claudia S.; Ekman, Matthias; van Gerven, Marcel A. J.; de Lange, Floris P.

    2016-01-01

    Visual information can alter auditory perception. This is clearly illustrated by the well-known McGurk illusion, where an auditory/aba/ and a visual /aga/ are merged to the percept of ‘ada’. It is less clear however whether such a change in perception may recalibrate subsequent perception. Here we asked whether the altered auditory perception due to the McGurk illusion affects subsequent auditory perception, i.e. whether this process of fusion may cause a recalibration of the auditory boundaries between phonemes. Participants categorized auditory and audiovisual speech stimuli as /aba/, /ada/ or /aga/ while activity patterns in their auditory cortices were recorded using fMRI. Interestingly, following a McGurk illusion, an auditory /aba/ was more often misperceived as ‘ada’. Furthermore, we observed a neural counterpart of this recalibration in the early auditory cortex. When the auditory input /aba/ was perceived as ‘ada’, activity patterns bore stronger resemblance to activity patterns elicited by /ada/ sounds than when they were correctly perceived as /aba/. Our results suggest that upon experiencing the McGurk illusion, the brain shifts the neural representation of an /aba/ sound towards /ada/, culminating in a recalibration in perception of subsequent auditory input. PMID:27611960

  6. Representation of Reward Feedback in Primate Auditory Cortex

    Directory of Open Access Journals (Sweden)

    Michael eBrosch

    2011-02-01

    Full Text Available It is well established that auditory cortex is plastic on different time scales and that this plasticity is driven by the reinforcement that is used to motivate subjects to learn or to perform an auditory task. Motivated by these findings, we study in detail properties of neuronal firing in auditory cortex that is related to reward feedback. We recorded from the auditory cortex of two monkeys while they were performing an auditory categorization task. Monkeys listened to a sequence of tones and had to signal when the frequency of adjacent tones stepped in downward direction, irrespective of the tone frequency and step size. Correct identifications were rewarded with either a large or a small amount of water. The size of reward depended on the monkeys' performance in the previous trial: it was large after a correct trial and small after an incorrect trial. The rewards served to maintain task performance. During task performance we found three successive periods of neuronal firing in auditory cortex that reflected (1 the reward expectancy for each trial, (2 the reward size received and (3 the mismatch between the expected and delivered reward. These results, together with control experiments suggest that auditory cortex receives reward feedback that could be used to adapt auditory cortex to task requirements. Additionally, the results presented here extend previous observations of non-auditory roles of auditory cortex and shows that auditory cortex is even more cognitively influenced than lately recognized.

  7. Representation of reward feedback in primate auditory cortex.

    Science.gov (United States)

    Brosch, Michael; Selezneva, Elena; Scheich, Henning

    2011-01-01

    It is well established that auditory cortex is plastic on different time scales and that this plasticity is driven by the reinforcement that is used to motivate subjects to learn or to perform an auditory task. Motivated by these findings, we study in detail properties of neuronal firing in auditory cortex that is related to reward feedback. We recorded from the auditory cortex of two monkeys while they were performing an auditory categorization task. Monkeys listened to a sequence of tones and had to signal when the frequency of adjacent tones stepped in downward direction, irrespective of the tone frequency and step size. Correct identifications were rewarded with either a large or a small amount of water. The size of reward depended on the monkeys' performance in the previous trial: it was large after a correct trial and small after an incorrect trial. The rewards served to maintain task performance. During task performance we found three successive periods of neuronal firing in auditory cortex that reflected (1) the reward expectancy for each trial, (2) the reward-size received, and (3) the mismatch between the expected and delivered reward. These results, together with control experiments suggest that auditory cortex receives reward feedback that could be used to adapt auditory cortex to task requirements. Additionally, the results presented here extend previous observations of non-auditory roles of auditory cortex and shows that auditory cortex is even more cognitively influenced than lately recognized.

  8. Characterization of auditory synaptic inputs to gerbil perirhinal cortex

    Directory of Open Access Journals (Sweden)

    Vibhakar C Kotak

    2015-08-01

    Full Text Available The representation of acoustic cues involves regions downstream from the auditory cortex (ACx. One such area, the perirhinal cortex (PRh, processes sensory signals containing mnemonic information. Therefore, our goal was to assess whether PRh receives auditory inputs from the auditory thalamus (MG and ACx in an auditory thalamocortical brain slice preparation and characterize these afferent-driven synaptic properties. When the MG or ACx was electrically stimulated, synaptic responses were recorded from the PRh neurons. Blockade of GABA-A receptors dramatically increased the amplitude of evoked excitatory potentials. Stimulation of the MG or ACx also evoked calcium transients in most PRh neurons. Separately, when fluoro ruby was injected in ACx in vivo, anterogradely labeled axons and terminals were observed in the PRh. Collectively, these data show that the PRh integrates auditory information from the MG and ACx and that auditory driven inhibition dominates the postsynaptic responses in a non-sensory cortical region downstream from the auditory cortex.

  9. 3-D Color Wheels

    Science.gov (United States)

    DuBois, Ann

    2010-01-01

    The blending of information from an academic class with projects from art class can do nothing but strengthen the learning power of the student. Creating three-dimensional color wheels provides the perfect opportunity to combine basic geometry knowledge with color theory. In this article, the author describes how her seventh-grade painting…

  10. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses ... keratoconus have a new treatment option. The U.S. Food and Drug Administration (FDA) has approved corneal collagen ...

  11. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses ... Cheryl terHorst On one of his regular mid-day swims, 78-year old Leroy Muffler noticed a ...

  12. Dynamic egg color mimicry.

    Science.gov (United States)

    Hanley, Daniel; Šulc, Michal; Brennan, Patricia L R; Hauber, Mark E; Grim, Tomáš; Honza, Marcel

    2016-06-01

    Evolutionary hypotheses regarding the function of eggshell phenotypes, from solar protection through mimicry, have implicitly assumed that eggshell appearance remains static throughout the laying and incubation periods. However, recent research demonstrates that egg coloration changes over relatively short, biologically relevant timescales. Here, we provide the first evidence that such changes impact brood parasite-host eggshell color mimicry during the incubation stage. First, we use long-term data to establish how rapidly the Acrocephalus arundinaceus Linnaeus (great reed warbler) responded to natural parasitic eggs laid by the Cuculus canorus Linnaeus (common cuckoo). Most hosts rejected parasitic eggs just prior to clutch completion, but the host response period extended well into incubation (~10 days after clutch completion). Using reflectance spectrometry and visual modeling, we demonstrate that eggshell coloration in the great reed warbler and its brood parasite, the common cuckoo, changes rapidly, and the extent of eggshell color mimicry shifts dynamically over the host response period. Specifically, 4 days after being laid, the host should notice achromatic color changes to both cuckoo and warbler eggs, while chromatic color changes would be noticeable after 8 days. Furthermore, we demonstrate that the perceived match between host and cuckoo eggshell color worsened over the incubation period. These findings have important implications for parasite-host coevolution dynamics, because host egg discrimination may be aided by disparate temporal color changes in host and parasite eggs. PMID:27516874

  13. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are ... a new treatment option. The U.S. Food and Drug Administration (FDA) has approved corneal collagen cross-linking ( ...

  14. The Color of Lobsters

    NARCIS (Netherlands)

    Wijk, Arjan van

    2005-01-01

    Synthesis of 13C-enriched carotenoids. Carotenoids are natural colorants, ranging in color from pale yellow to deep purple, with important biological functions. Carotenoids in the human diet have a beneficial health effect, playing a role in the prevention of cardiovascular disease and cancer. To ge

  15. Gauge color codes

    DEFF Research Database (Denmark)

    Bombin Palomo, Hector

    2015-01-01

    Color codes are topological stabilizer codes with unusual transversality properties. Here I show that their group of transversal gates is optimal and only depends on the spatial dimension, not the local geometry. I also introduce a generalized, subsystem version of color codes. In 3D they allow the...

  16. Measuring Auditory Selective Attention using Frequency Tagging

    Directory of Open Access Journals (Sweden)

    Hari M Bharadwaj

    2014-02-01

    Full Text Available Frequency tagging of sensory inputs (presenting stimuli that fluctuate periodically at rates to which the cortex can phase lock has been used to study attentional modulation of neural responses to inputs in different sensory modalities. For visual inputs, the visual steady-state response (VSSR at the frequency modulating an attended object is enhanced, while the VSSR to a distracting object is suppressed. In contrast, the effect of attention on the auditory steady-state response (ASSR is inconsistent across studies. However, most auditory studies analyzed results at the sensor level or used only a small number of equivalent current dipoles to fit cortical responses. In addition, most studies of auditory spatial attention used dichotic stimuli (independent signals at the ears rather than more natural, binaural stimuli. Here, we asked whether these methodological choices help explain discrepant results. Listeners attended to one of two competing speech streams, one simulated from the left and one from the right, that were modulated at different frequencies. Using distributed source modeling of magnetoencephalography results, we estimate how spatially directed attention modulates the ASSR in neural regions across the whole brain. Attention enhances the ASSR power at the frequency of the attended stream in the contralateral auditory cortex. The attended-stream modulation frequency also drives phase-locked responses in the left (but not right precentral sulcus (lPCS, a region implicated in control of eye gaze and visual spatial attention. Importantly, this region shows no phase locking to the distracting stream suggesting that the lPCS in engaged in an attention-specific manner. Modeling results that take account of the geometry and phases of the cortical sources phase locked to the two streams (including hemispheric asymmetry of lPCS activity help partly explain why past ASSR studies of auditory spatial attention yield seemingly contradictory

  17. "Focal" Color Areas and the Development of Color Names

    Science.gov (United States)

    Heider, Eleanor Rosch

    1971-01-01

    Three experiments using 3- and 4-year-olds as subjects tested the hypothesis that focal colors are more salient than nonfocal colors for young children and are the areas to which color names initially become attached. (NH)

  18. Hear no evil: The effect of auditory warning signals on avian innate avoidance, learned avoidance and memory

    Directory of Open Access Journals (Sweden)

    Emma C. SIDDALL, Nicola M. MARPLES

    2011-04-01

    Full Text Available Many aposematic insect species advertise their toxicity to potential predators using olfactory and auditory signals, in addition to visual signals, to produce a multimodal warning display. The olfactory signals in these displays may have interesting effects, such as eliciting innate avoidance against novel colored prey, or improving learning and memory of defended prey. However, little is known about the effects of such ancillary signals when they are auditory rather than olfactory. The few studies that have investigated this question have provided conflicting results. The current study sought to clarify and extend understanding of the effects of prey auditory signals on avian predator responses. The domestic chick Gallus gallus domesticus was used as a model avian predator to examine how the defensive buzzing sound of a bumblebee Bombus terrestris affected the chick’s innate avoidance behavior, and the learning and memory of prey avoidance. The results demonstrate that the buzzing sound had no effect on the predator’s responses to unpalatable aposematically colored crumbs, suggesting that the agitated buzzing of B. terrestris may provide no additional protection from avian predators [Current Zoology 57 (2: 197–207, 2011].

  19. Hear no evil:The effect of auditory warning signals on avian innate avoidance,learned avoidance and memory

    Institute of Scientific and Technical Information of China (English)

    Emma C.SIDDALL; Nicola M.MARPLES

    2011-01-01

    Many aposematic insect species advertise their toxicity to potential predators using olfactory and auditory signals,in addition to visual signals,to produce a multimodal warning display.The olfactory signals in these displays may have interesting effects,such as eliciting innate avoidance against novel colored prey,or improving learning and memory of defended prey.However,little is known about the effects of such ancillary signals when they are auditory rather than olfactory.The few studies that have investigated this question have provided confficting results.The current study sought to clarify and extend understanding of the effects of prey auditory signals on avian predator responses.The domestic chick Gallus gallus domesticus was used as a model avian predator to examine how the defensive buzzing sound of a bumblebee Bombus terrestris affected the chick's innate avoidance behavior,and the learning and memory of prey avoidance.The resuits demonstrate that the buzzing sound had no effect on the predator's responses to unpalalable aposematically colored crumbs,suggesting that the agitated buzzing of B.terrestris may provide no additional protection from avian predators.

  20. Attention Modulates the Auditory Cortical Processing of Spatial and Category Cues in Naturalistic Auditory Scenes

    Science.gov (United States)

    Renvall, Hanna; Staeren, Noël; Barz, Claudia S.; Ley, Anke; Formisano, Elia

    2016-01-01

    This combined fMRI and MEG study investigated brain activations during listening and attending to natural auditory scenes. We first recorded, using in-ear microphones, vocal non-speech sounds, and environmental sounds that were mixed to construct auditory scenes containing two concurrent sound streams. During the brain measurements, subjects attended to one of the streams while spatial acoustic information of the scene was either preserved (stereophonic sounds) or removed (monophonic sounds). Compared to monophonic sounds, stereophonic sounds evoked larger blood-oxygenation-level-dependent (BOLD) fMRI responses in the bilateral posterior superior temporal areas, independent of which stimulus attribute the subject was attending to. This finding is consistent with the functional role of these regions in the (automatic) processing of auditory spatial cues. Additionally, significant differences in the cortical activation patterns depending on the target of attention were observed. Bilateral planum temporale and inferior frontal gyrus were preferentially activated when attending to stereophonic environmental sounds, whereas when subjects attended to stereophonic voice sounds, the BOLD responses were larger at the bilateral middle superior temporal gyrus and sulcus, previously reported to show voice sensitivity. In contrast, the time-resolved MEG responses were stronger for mono- than stereophonic sounds in the bilateral auditory cortices at ~360 ms after the stimulus onset when attending to the voice excerpts within the combined sounds. The observed effects suggest that during the segregation of auditory objects from the auditory background, spatial sound cues together with other relevant temporal and spectral cues are processed in an attention-dependent manner at the cortical locations generally involved in sound recognition. More synchronous neuronal activation during monophonic than stereophonic sound processing, as well as (local) neuronal inhibitory mechanisms in

  1. Theoretical aspects of color vision

    Science.gov (United States)

    Wolbarsht, M. L.

    1972-01-01

    The three color receptors of Young-Helmholtz and the opponent colors type of information processing postulated by Hering are both present in the human visual system. This mixture accounts for both the phenomena of color matching or hue discrimination and such perceptual qualities of color as the division of the spectrum into color bands. The functioning of the cells in the visual system, especially within the retina, and the relation of this function to color perception are discussed.

  2. Shaping the aging brain: Role of auditory input patterns in the emergence of auditory cortical impairments

    Directory of Open Access Journals (Sweden)

    Brishna Soraya Kamal

    2013-09-01

    Full Text Available Age-related impairments in the primary auditory cortex (A1 include poor tuning selectivity, neural desynchronization and degraded responses to low-probability sounds. These changes have been largely attributed to reduced inhibition in the aged brain, and are thought to contribute to substantial hearing impairment in both humans and animals. Since many of these changes can be partially reversed with auditory training, it has been speculated that they might not be purely degenerative, but might rather represent negative plastic adjustments to noisy or distorted auditory signals reaching the brain. To test this hypothesis, we examined the impact of exposing young adult rats to 8 weeks of low-grade broadband noise on several aspects of A1 function and structure. We then characterized the same A1 elements in aging rats for comparison. We found that the impact of noise exposure on A1 tuning selectivity, temporal processing of auditory signal and responses to oddball tones was almost indistinguishable from the effect of natural aging. Moreover, noise exposure resulted in a reduction in the population of parvalbumin inhibitory interneurons and cortical myelin as previously documented in the aged group. Most of these changes reversed after returning the rats to a quiet environment. These results support the hypothesis that age-related changes in A1 have a strong activity-dependent component and indicate that the presence or absence of clear auditory input patterns might be a key factor in sustaining adult A1 function.

  3. Selective memory retrieval of auditory what and auditory where involves the ventrolateral prefrontal cortex.

    Science.gov (United States)

    Kostopoulos, Penelope; Petrides, Michael

    2016-02-16

    There is evidence from the visual, verbal, and tactile memory domains that the midventrolateral prefrontal cortex plays a critical role in the top-down modulation of activity within posterior cortical areas for the selective retrieval of specific aspects of a memorized experience, a functional process often referred to as active controlled retrieval. In the present functional neuroimaging study, we explore the neural bases of active retrieval for auditory nonverbal information, about which almost nothing is known. Human participants were scanned with functional magnetic resonance imaging (fMRI) in a task in which they were presented with short melodies from different locations in a simulated virtual acoustic environment within the scanner and were then instructed to retrieve selectively either the particular melody presented or its location. There were significant activity increases specifically within the midventrolateral prefrontal region during the selective retrieval of nonverbal auditory information. During the selective retrieval of information from auditory memory, the right midventrolateral prefrontal region increased its interaction with the auditory temporal region and the inferior parietal lobule in the right hemisphere. These findings provide evidence that the midventrolateral prefrontal cortical region interacts with specific posterior cortical areas in the human cerebral cortex for the selective retrieval of object and location features of an auditory memory experience.

  4. An Auditory Model with Hearing Loss

    DEFF Research Database (Denmark)

    Nielsen, Lars Bramsløw

    An auditory model based on the psychophysics of hearing has been developed and tested. The model simulates the normal ear or an impaired ear with a given hearing loss. Based on reviews of the current literature, the frequency selectivity and loudness growth as functions of threshold and stimulus...... level have been found and implemented in the model. The auditory model was verified against selected results from the literature, and it was confirmed that the normal spread of masking and loudness growth could be simulated in the model. The effects of hearing loss on these parameters was also...... in qualitative agreement with recent findings. The temporal properties of the ear have currently not been included in the model. As an example of a real-world application of the model, loudness spectrograms for a speech utterance were presented. By introducing hearing loss, the speech sounds became less audible...

  5. Central auditory neurons have composite receptive fields.

    Science.gov (United States)

    Kozlov, Andrei S; Gentner, Timothy Q

    2016-02-01

    High-level neurons processing complex, behaviorally relevant signals are sensitive to conjunctions of features. Characterizing the receptive fields of such neurons is difficult with standard statistical tools, however, and the principles governing their organization remain poorly understood. Here, we demonstrate multiple distinct receptive-field features in individual high-level auditory neurons in a songbird, European starling, in response to natural vocal signals (songs). We then show that receptive fields with similar characteristics can be reproduced by an unsupervised neural network trained to represent starling songs with a single learning rule that enforces sparseness and divisive normalization. We conclude that central auditory neurons have composite receptive fields that can arise through a combination of sparseness and normalization in neural circuits. Our results, along with descriptions of random, discontinuous receptive fields in the central olfactory neurons in mammals and insects, suggest general principles of neural computation across sensory systems and animal classes. PMID:26787894

  6. Deafness in cochlear and auditory nerve disorders.

    Science.gov (United States)

    Hopkins, Kathryn

    2015-01-01

    Sensorineural hearing loss is the most common type of hearing impairment worldwide. It arises as a consequence of damage to the cochlea or auditory nerve, and several structures are often affected simultaneously. There are many causes, including genetic mutations affecting the structures of the inner ear, and environmental insults such as noise, ototoxic substances, and hypoxia. The prevalence increases dramatically with age. Clinical diagnosis is most commonly accomplished by measuring detection thresholds and comparing these to normative values to determine the degree of hearing loss. In addition to causing insensitivity to weak sounds, sensorineural hearing loss has a number of adverse perceptual consequences, including loudness recruitment, poor perception of pitch and auditory space, and difficulty understanding speech, particularly in the presence of background noise. The condition is usually incurable; treatment focuses on restoring the audibility of sounds made inaudible by hearing loss using either hearing aids or cochlear implants.

  7. Anatomy and Physiology of the Auditory Tracts

    Directory of Open Access Journals (Sweden)

    Mohammad hosein Hekmat Ara

    1999-03-01

    Full Text Available Hearing is one of the excel sense of human being. Sound waves travel through the medium of air and enter the ear canal and then hit the tympanic membrane. Middle ear transfer almost 60-80% of this mechanical energy to the inner ear by means of “impedance matching”. Then, the sound energy changes to traveling wave and is transferred based on its specific frequency and stimulates organ of corti. Receptors in this organ and their synapses transform mechanical waves to the neural waves and transfer them to the brain. The central nervous system tract of conducting the auditory signals in the auditory cortex will be explained here briefly.

  8. Delayed auditory feedback in polyglot simultaneous interpreters.

    Science.gov (United States)

    Fabbro, F; Darò, V

    1995-03-01

    Twelve polyglot students of simultaneous interpretation and 12 controls (students of the faculty of Medicine) were submitted to a task of verbal fluency under amplified normal auditory feedback (NAF) and under three delayed auditory feedback (DAF) conditions with three different delay intervals (150, 200, and 250 msec). The control group showed a significant reduction in verbal fluency and a significant increase in the number of mistakes in all three DAF conditions. The interpreters' group, however, did not show any significant speech disruption neither in the subjects' mother tongue (L1) nor in their second language (L2) across all DAF conditions. Interpreters' general high verbal fluency along with their ability to pay less attention to their own verbal output make them more resistant to the interfering effects of DAF on speech. PMID:7757448

  9. Color vision test

    Science.gov (United States)

    ... vision problems: Achromatopsia -- complete color blindness , seeing only shades of gray Deuteranopia -- difficulty telling the difference between red/purple and green/purple Protanopia -- difficulty telling the difference between blue/ ...

  10. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... like a suction cup." Halloween is a popular time for people to use colored contact lenses to ... wear costume contact lenses for Halloween or any time of year, follow these guidelines: Get an eye ...

  11. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... popping touch. But colored contact lenses are popular year-round, not just at Halloween. But few know ... contact lenses for Halloween or any time of year, follow these guidelines: Get an eye exam from ...

  12. Phoenix Color Targets

    Science.gov (United States)

    2008-01-01

    These images of three Phoenix color targets were taken on sols 1 and 2 by the Surface Stereo Imager (SSI) on board the Phoenix lander. The bottom target was imaged in approximate color (SSI's red, green, and blue filters: 600, 530, and 480 nanometers), while the others were imaged with an infrared filter (750 nanometers). All of them will be imaged many times over the mission to monitor the color calibration of the camera. The two at the top show grains 2 to 3 millimeters in size that were likely lifted to the Phoenix deck during landing. Each of the large color chips on each target contains a strong magnet to protect the interior material from Mars' magnetic dust. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  13. The color of money

    DEFF Research Database (Denmark)

    Ásgeirsson, Árni Gunnar; Kristjánsson, Árni; Einarsdóttir, Kristin Vala;

    2014-01-01

    of attention are affected by reward, and whether the effect involves general enhancement or is specific to discrete components of attention. Observers viewed brief displays of differentially colored letters and reported their identity. Each color signified a consistent monetary value and we measured...... the accuracy of identification under different color-pairing conditions. At the end of the session, observers were paid the balance earned during the experiment. By fitting a model based on the Theory of Visual Attention (Bundesen, 1990) to the data, we estimated processing speed, selectivity, visual short......, by including conditions with color-contingent negative values. This gave an opportunity to compare high-gain with high-loss conditions. We found clear effects of value on selectivity when comparing high- and low-value conditions. When comparing equally valuable high-loss and high-gain conditions there were...

  14. Neutron color image intensifier

    International Nuclear Information System (INIS)

    Neutron radiography is expanding from the conventional reactor based imaging to the imaging by accelerator based pulsed neutron source. Among them, an expectation for image intensifier technology is increasing especially for video rate dynamic image detection or time dependent imaging in a pulsed neutron source. Based on the X-ray color image intensifier technology, Toshiba has developed neutron color image intensifiers as a powerful imaging tool for dynamic and time dependent neutron radiographics. In this paper, the construction and the feature of the developed neutron color image intensifier and some examples of neutron images are presented. I would be grateful if this paper helps for wide application of neutron color image intensifiers. (author)

  15. A Colorful Equatorial Wonderland

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Papua New Guinea (PNG) is one of the least visited countries in the world... a last frontier for international travelers. PNG is a colorful equatorial wonderland as well as a living example of human's culture 1000 years ago.

  16. THE COLOR GLASS CONDENSATE.

    Energy Technology Data Exchange (ETDEWEB)

    MCLERRAN,L.

    2001-08-26

    The Color Glass Condensate is a state of high density gluonic matter which controls the high energy limit of hadronic interactions. Its properties are important for the initial conditions for matter produced at RHIC.

  17. Skin color - patchy

    Science.gov (United States)

    ... such as from the sun) Exposure to heavy metals Changes in hormone levels Exposure to sun or ultraviolet (UV) light, especially after taking a medicine called psoralens, may increase skin color (pigmentation). Increased ...

  18. Response recovery in the locust auditory pathway.

    Science.gov (United States)

    Wirtssohn, Sarah; Ronacher, Bernhard

    2016-01-01

    Temporal resolution and the time courses of recovery from acute adaptation of neurons in the auditory pathway of the grasshopper Locusta migratoria were investigated with a response recovery paradigm. We stimulated with a series of single click and click pair stimuli while performing intracellular recordings from neurons at three processing stages: receptors and first and second order interneurons. The response to the second click was expressed relative to the single click response. This allowed the uncovering of the basic temporal resolution in these neurons. The effect of adaptation increased with processing layer. While neurons in the auditory periphery displayed a steady response recovery after a short initial adaptation, many interneurons showed nonlinear effects: most prominent a long-lasting suppression of the response to the second click in a pair, as well as a gain in response if a click was preceded by a click a few milliseconds before. Our results reveal a distributed temporal filtering of input at an early auditory processing stage. This set of specified filters is very likely homologous across grasshopper species and thus forms the neurophysiological basis for extracting relevant information from a variety of different temporal signals. Interestingly, in terms of spike timing precision neurons at all three processing layers recovered very fast, within 20 ms. Spike waveform analysis of several neuron types did not sufficiently explain the response recovery profiles implemented in these neurons, indicating that temporal resolution in neurons located at several processing layers of the auditory pathway is not necessarily limited by the spike duration and refractory period.

  19. Neural correlates of auditory scale illusion.

    Science.gov (United States)

    Kuriki, Shinya; Numao, Ryousuke; Nemoto, Iku

    2016-09-01

    The auditory illusory perception "scale illusion" occurs when ascending and descending musical scale tones are delivered in a dichotic manner, such that the higher or lower tone at each instant is presented alternately to the right and left ears. Resulting tone sequences have a zigzag pitch in one ear and the reversed (zagzig) pitch in the other ear. Most listeners hear illusory smooth pitch sequences of up-down and down-up streams in the two ears separated in higher and lower halves of the scale. Although many behavioral studies have been conducted, how and where in the brain the illusory percept is formed have not been elucidated. In this study, we conducted functional magnetic resonance imaging using sequential tones that induced scale illusion (ILL) and those that mimicked the percept of scale illusion (PCP), and we compared the activation responses evoked by those stimuli by region-of-interest analysis. We examined the effects of adaptation, i.e., the attenuation of response that occurs when close-frequency sounds are repeated, which might interfere with the changes in activation by the illusion process. Results of the activation difference of the two stimuli, measured at varied tempi of tone presentation, in the superior temporal auditory cortex were not explained by adaptation. Instead, excess activation of the ILL stimulus from the PCP stimulus at moderate tempi (83 and 126 bpm) was significant in the posterior auditory cortex with rightward superiority, while significant prefrontal activation was dominant at the highest tempo (245 bpm). We suggest that the area of the planum temporale posterior to the primary auditory cortex is mainly involved in the illusion formation, and that the illusion-related process is strongly dependent on the rate of tone presentation. PMID:27292114

  20. Inhibition in the Human Auditory Cortex

    OpenAIRE

    Koji Inui; Kei Nakagawa; Makoto Nishihara; Eishi Motomura; Ryusuke Kakigi

    2016-01-01

    Despite their indispensable roles in sensory processing, little is known about inhibitory interneurons in humans. Inhibitory postsynaptic potentials cannot be recorded non-invasively, at least in a pure form, in humans. We herein sought to clarify whether prepulse inhibition (PPI) in the auditory cortex reflected inhibition via interneurons using magnetoencephalography. An abrupt increase in sound pressure by 10 dB in a continuous sound was used to evoke the test response, and PPI was observe...

  1. Lesions in the external auditory canal

    Directory of Open Access Journals (Sweden)

    Priyank S Chatra

    2011-01-01

    Full Text Available The external auditory canal is an S- shaped osseo-cartilaginous structure that extends from the auricle to the tympanic membrane. Congenital, inflammatory, neoplastic, and traumatic lesions can affect the EAC. High-resolution CT is well suited for the evaluation of the temporal bone, which has a complex anatomy with multiple small structures. In this study, we describe the various lesions affecting the EAC.

  2. Midbrain auditory selectivity to natural sounds.

    Science.gov (United States)

    Wohlgemuth, Melville J; Moss, Cynthia F

    2016-03-01

    This study investigated auditory stimulus selectivity in the midbrain superior colliculus (SC) of the echolocating bat, an animal that relies on hearing to guide its orienting behaviors. Multichannel, single-unit recordings were taken across laminae of the midbrain SC of the awake, passively listening big brown bat, Eptesicus fuscus. Species-specific frequency-modulated (FM) echolocation sound sequences with dynamic spectrotemporal features served as acoustic stimuli along with artificial sound sequences matched in bandwidth, amplitude, and duration but differing in spectrotemporal structure. Neurons in dorsal sensory regions of the bat SC responded selectively to elements within the FM sound sequences, whereas neurons in ventral sensorimotor regions showed broad response profiles to natural and artificial stimuli. Moreover, a generalized linear model (GLM) constructed on responses in the dorsal SC to artificial linear FM stimuli failed to predict responses to natural sounds and vice versa, but the GLM produced accurate response predictions in ventral SC neurons. This result suggests that auditory selectivity in the dorsal extent of the bat SC arises through nonlinear mechanisms, which extract species-specific sensory information. Importantly, auditory selectivity appeared only in responses to stimuli containing the natural statistics of acoustic signals used by the bat for spatial orientation-sonar vocalizations-offering support for the hypothesis that sensory selectivity enables rapid species-specific orienting behaviors. The results of this study are the first, to our knowledge, to show auditory spectrotemporal selectivity to natural stimuli in SC neurons and serve to inform a more general understanding of mechanisms guiding sensory selectivity for natural, goal-directed orienting behaviors.

  3. Predictive uncertainty in auditory sequence processing

    OpenAIRE

    Niels Chr.Hansen; MarcusT.Pearce

    2014-01-01

    Previous studies of auditory expectation have focused on the expectedness perceived by listeners retrospectively in response to events. In contrast, this research examines predictive uncertainty - a property of listeners’ prospective state of expectation prior to the onset of an event. We examine the information-theoretic concept of Shannon entropy as a model of predictive uncertainty in music cognition. This is motivated by the Statistical Learning Hypothesis, which proposes that schematic e...

  4. Sonic morphology: Aesthetic dimensional auditory spatial awareness

    Science.gov (United States)

    Whitehouse, Martha M.

    The sound and ceramic sculpture installation, " Skirting the Edge: Experiences in Sound & Form," is an integration of art and science demonstrating the concept of sonic morphology. "Sonic morphology" is herein defined as aesthetic three-dimensional auditory spatial awareness. The exhibition explicates my empirical phenomenal observations that sound has a three-dimensional form. Composed of ceramic sculptures that allude to different social and physical situations, coupled with sound compositions that enhance and create a three-dimensional auditory and visual aesthetic experience (see accompanying DVD), the exhibition supports the research question, "What is the relationship between sound and form?" Precisely how people aurally experience three-dimensional space involves an integration of spatial properties, auditory perception, individual history, and cultural mores. People also utilize environmental sound events as a guide in social situations and in remembering their personal history, as well as a guide in moving through space. Aesthetically, sound affects the fascination, meaning, and attention one has within a particular space. Sonic morphology brings art forms such as a movie, video, sound composition, and musical performance into the cognitive scope by generating meaning from the link between the visual and auditory senses. This research examined sonic morphology as an extension of musique concrete, sound as object, originating in Pierre Schaeffer's work in the 1940s. Pointing, as John Cage did, to the corporeal three-dimensional experience of "all sound," I composed works that took their total form only through the perceiver-participant's participation in the exhibition. While contemporary artist Alvin Lucier creates artworks that draw attention to making sound visible, "Skirting the Edge" engages the perceiver-participant visually and aurally, leading to recognition of sonic morphology.

  5. Relighting multiple color textures

    Institute of Scientific and Technical Information of China (English)

    DIAO Chang-yu; LU Dong-ming; LIU Gang

    2005-01-01

    With the development of digital library technology, library books made of paper can be digital released and read, and Endangered Cultural Heritages can be preserved. Traditional library's contents and functions can be greatly enhanced by digital technologies. For these new library objects, the primary key problem is precisely reconstructing their 3D models. When constructing complete 3D models, multiple color texture maps are often necessary. A commonly encountered problem uncounted during fusing of textures from multiple color images is color distortion. Each texture of a single 3D model may be obtained under possibly different lighting conditions and color response of the camera. To remove any visible seam and improve color consistency between the textures while avoiding color distortion, we propose a new efficient algorithm to relight all the texture images globally,spread residual light difference, and recolor each image by homogeneous transformation. A relative illumination model was adopted to obtain the relighting function. We choose lαβ color space with minimal correlation between channels for many natural scenes, for calculating the relighting result. Looking into two overlapped images A and B, we can pairwise relight B into A's luminosity condition in two steps. We first scale B's l channel by the lA/lB ratio of the overlapped region. We can assume A and B are in a same color plane now. Then a homogeneous transformation is applied to B's α and β channels which moves B into A's hue and saturation condition. For multiple overlapped color textures, a patch based weighted global relighting method was proposed to minimize the total color difference. The pairwise relighting method was used between each two overlapped images, and the difference in every overlapped region after relighting was weighted and summed up to construct an energy value. We used Nelder-Mead method to find a minimal energy value and the relighting parameters for every image. After

  6. Color names, color categories, and color-cued visual search: Sometimes, color perception is not categorical

    OpenAIRE

    Brown, Angela M.; Lindsey, Delwin T.; Guckes, Kevin M

    2011-01-01

    The relation between colors and their names is a classic case-study for investigating the Sapir-Whorf hypothesis that categorical perception is imposed on perception by language. Here, we investigate the Sapir-Whorf prediction that visual search for a green target presented among blue distractors (or vice versa) should be faster than search for a green target presented among distractors of a different color of green (or for a blue target among different blue distractors). Gilbert, Regier, Kay...

  7. Unfolding the color code

    OpenAIRE

    Kubica, Aleksander; Yoshida, Beni; Pastawski, Fernando

    2015-01-01

    The topological color code and the toric code are two leading candidates for realizing fault-tolerant quantum computation. Here we show that the color code on a $d$-dimensional closed manifold is equivalent to multiple decoupled copies of the $d$-dimensional toric code up to local unitary transformations and adding or removing ancilla qubits. Our result not only generalizes the proven equivalence for $d=2$, but also provides an explicit recipe of how to decouple independent components of the ...

  8. Stroke caused auditory attention deficits in children

    Directory of Open Access Journals (Sweden)

    Karla Maria Ibraim da Freiria Elias

    2013-01-01

    Full Text Available OBJECTIVE: To verify the auditory selective attention in children with stroke. METHODS: Dichotic tests of binaural separation (non-verbal and consonant-vowel and binaural integration - digits and Staggered Spondaic Words Test (SSW - were applied in 13 children (7 boys, from 7 to 16 years, with unilateral stroke confirmed by neurological examination and neuroimaging. RESULTS: The attention performance showed significant differences in comparison to the control group in both kinds of tests. In the non-verbal test, identifications the ear opposite the lesion in the free recall stage was diminished and, in the following stages, a difficulty in directing attention was detected. In the consonant- vowel test, a modification in perceptual asymmetry and difficulty in focusing in the attended stages was found. In the digits and SSW tests, ipsilateral, contralateral and bilateral deficits were detected, depending on the characteristics of the lesions and demand of the task. CONCLUSION: Stroke caused auditory attention deficits when dealing with simultaneous sources of auditory information.

  9. Hierarchical processing of auditory objects in humans.

    Directory of Open Access Journals (Sweden)

    Sukhbinder Kumar

    2007-06-01

    Full Text Available This work examines the computational architecture used by the brain during the analysis of the spectral envelope of sounds, an important acoustic feature for defining auditory objects. Dynamic causal modelling and Bayesian model selection were used to evaluate a family of 16 network models explaining functional magnetic resonance imaging responses in the right temporal lobe during spectral envelope analysis. The models encode different hypotheses about the effective connectivity between Heschl's Gyrus (HG, containing the primary auditory cortex, planum temporale (PT, and superior temporal sulcus (STS, and the modulation of that coupling during spectral envelope analysis. In particular, we aimed to determine whether information processing during spectral envelope analysis takes place in a serial or parallel fashion. The analysis provides strong support for a serial architecture with connections from HG to PT and from PT to STS and an increase of the HG to PT connection during spectral envelope analysis. The work supports a computational model of auditory object processing, based on the abstraction of spectro-temporal "templates" in the PT before further analysis of the abstracted form in anterior temporal lobe areas.

  10. Concentric scheme of monkey auditory cortex

    Science.gov (United States)

    Kosaki, Hiroko; Saunders, Richard C.; Mishkin, Mortimer

    2003-04-01

    The cytoarchitecture of the rhesus monkey's auditory cortex was examined using immunocytochemical staining with parvalbumin, calbindin-D28K, and SMI32, as well as staining for cytochrome oxidase (CO). The results suggest that Kaas and Hackett's scheme of the auditory cortices can be extended to include five concentric rings surrounding an inner core. The inner core, containing areas A1 and R, is the most densely stained with parvalbumin and CO and can be separated on the basis of laminar patterns of SMI32 staining into lateral and medial subdivisions. From the inner core to the fifth (outermost) ring, parvalbumin staining gradually decreases and calbindin staining gradually increases. The first ring corresponds to Kaas and Hackett's auditory belt, and the second, to their parabelt. SMI32 staining revealed a clear border between these two. Rings 2 through 5 extend laterally into the dorsal bank of the superior temporal sulcus. The results also suggest that the rostral tip of the outermost ring adjoins the rostroventral part of the insula (area Pro) and the temporal pole, while the caudal tip adjoins the ventral part of area 7a.

  11. Auditory perception of a human walker.

    Science.gov (United States)

    Cottrell, David; Campbell, Megan E J

    2014-01-01

    When one hears footsteps in the hall, one is able to instantly recognise it as a person: this is an everyday example of auditory biological motion perception. Despite the familiarity of this experience, research into this phenomenon is in its infancy compared with visual biological motion perception. Here, two experiments explored sensitivity to, and recognition of, auditory stimuli of biological and nonbiological origin. We hypothesised that the cadence of a walker gives rise to a temporal pattern of impact sounds that facilitates the recognition of human motion from auditory stimuli alone. First a series of detection tasks compared sensitivity with three carefully matched impact sounds: footsteps, a ball bouncing, and drumbeats. Unexpectedly, participants were no more sensitive to footsteps than to impact sounds of nonbiological origin. In the second experiment participants made discriminations between pairs of the same stimuli, in a series of recognition tasks in which the temporal pattern of impact sounds was manipulated to be either that of a walker or the pattern more typical of the source event (a ball bouncing or a drumbeat). Under these conditions, there was evidence that both temporal and nontemporal cues were important in recognising theses stimuli. It is proposed that the interval between footsteps, which reflects a walker's cadence, is a cue for the recognition of the sounds of a human walking.

  12. Mechanisms of auditory verbal hallucination in schizophrenia

    Directory of Open Access Journals (Sweden)

    Raymond eCho

    2013-11-01

    Full Text Available Recent work on the mechanisms underlying auditory verbal hallucination (AVH has been heavily informed by self-monitoring accounts that postulate defects in an internal monitoring mechanism as the basis of AVH. A more neglected alternative is an account focusing on defects in auditory processing, namely a spontaneous activation account of auditory activity underlying AVH. Science is often aided by putting theories in competition. Accordingly, a discussion that systematically contrasts the two models of AVH can generate sharper questions that will lead to new avenues of investigation. In this paper, we provide such a theoretical discussion of the two models, drawing strong contrasts between them. We identify a set of challenges for the self-monitoring account and argue that the spontaneous activation account has much in favor of it and should be the default account. Our theoretical overview leads to new questions and issues regarding the explanation of AVH as a subjective phenomenon and its neural basis. Accordingly, we suggest a set of experimental strategies to dissect the underlying mechanisms of AVH in light of the two competing models.

  13. Mechanisms of auditory verbal hallucination in schizophrenia.

    Science.gov (United States)

    Cho, Raymond; Wu, Wayne

    2013-01-01

    Recent work on the mechanisms underlying auditory verbal hallucination (AVH) has been heavily informed by self-monitoring accounts that postulate defects in an internal monitoring mechanism as the basis of AVH. A more neglected alternative is an account focusing on defects in auditory processing, namely a spontaneous activation account of auditory activity underlying AVH. Science is often aided by putting theories in competition. Accordingly, a discussion that systematically contrasts the two models of AVH can generate sharper questions that will lead to new avenues of investigation. In this paper, we provide such a theoretical discussion of the two models, drawing strong contrasts between them. We identify a set of challenges for the self-monitoring account and argue that the spontaneous activation account has much in favor of it and should be the default account. Our theoretical overview leads to new questions and issues regarding the explanation of AVH as a subjective phenomenon and its neural basis. Accordingly, we suggest a set of experimental strategies to dissect the underlying mechanisms of AVH in light of the two competing models. PMID:24348430

  14. Central auditory masking by an illusory tone.

    Directory of Open Access Journals (Sweden)

    Christopher J Plack

    Full Text Available Many natural sounds fluctuate over time. The detectability of sounds in a sequence can be reduced by prior stimulation in a process known as forward masking. Forward masking is thought to reflect neural adaptation or neural persistence in the auditory nervous system, but it has been unclear where in the auditory pathway this processing occurs. To address this issue, the present study used a "Huggins pitch" stimulus, the perceptual effects of which depend on central auditory processing. Huggins pitch is an illusory tonal sensation produced when the same noise is presented to the two ears except for a narrow frequency band that is different (decorrelated between the ears. The pitch sensation depends on the combination of the inputs to the two ears, a process that first occurs at the level of the superior olivary complex in the brainstem. Here it is shown that a Huggins pitch stimulus produces more forward masking in the frequency region of the decorrelation than a noise stimulus identical to the Huggins-pitch stimulus except with perfect correlation between the ears. This stimulus has a peripheral neural representation that is identical to that of the Huggins-pitch stimulus. The results show that processing in, or central to, the superior olivary complex can contribute to forward masking in human listeners.

  15. Novikov Color Algebra and Tortken Color Algebra%Novikov Color 代数与 Tortken Color 代数

    Institute of Scientific and Technical Information of China (English)

    高秀娟; 徐丽媛

    2016-01-01

    Three concepts of Novikov color algebra,Tortken color algebra and Jordan color algebra were defined,then the relations among three algebras were discussed.We gave the basic properties of Novikov color algebra and Tortken color algebra.Then we proved a Tortken color algebra with an identity element is both associative and color commutative.We also showed how to use Novikov color algebra to construct a Tortken color algebra.%给出 Novikov color 代数、Tortken color 和 Jordan color 代数的定义,并讨论它们之间的关系,证明了有单位元的 Tortken color 代数是结合的,也是 color 交换的。给出 Novikov color 代数和 Tortken color 代数的基本性质以及利用 Novikov color 代数构造 Tortken color代数的方法。

  16. Color planner for designers based on color emotions

    Science.gov (United States)

    Cheng, Ka-Man; Xin, John H.; Taylor, Gail

    2002-06-01

    During the color perception process, an associated feeling or emotion is induced in our brains, and this kind of emotion is termed as 'color emotion.' The researchers in the field of color emotions have put many efforts in quantifying color emotions with the standard color specifications and evaluating the influence of hue, lightness and chroma to the color emotions of human beings. In this study, a color planner was derived according to these findings so that the correlation of color emotions and standard color specifications was clearly indicated. Since people of different nationalities usually have different color emotions as different cultural and traditional backgrounds, the subjects in this study were all native Hong Kong Chinese and the color emotion words were all written in Chinese language in the visual assessments. Through the color planner, the designers from different areas, no matter fashion, graphic, interior or web site etc., can select suitable colors for inducing target color emotions to the customers or product-users since different colors convey different meanings to them. In addition, the designers can enhance the functionality and increase the attractiveness of their designed products by selecting suitable colors.

  17. Luminance contours can gate afterimage colors and 'real' colors

    NARCIS (Netherlands)

    Anstis, S.; Vergeer, M.L.T.; Lier, R.J. van

    2012-01-01

    It has long been known that colored images may elicit afterimages in complementary colors. We have already shown (Van Lier, Vergeer, & Anstis, 2009) that one and the same adapting image may result in different afterimage colors, depending on the test contours presented after the colored image. The c

  18. Auditory temporal processing skills in musicians with dyslexia.

    Science.gov (United States)

    Bishop-Liebler, Paula; Welch, Graham; Huss, Martina; Thomson, Jennifer M; Goswami, Usha

    2014-08-01

    The core cognitive difficulty in developmental dyslexia involves phonological processing, but adults and children with dyslexia also have sensory impairments. Impairments in basic auditory processing show particular links with phonological impairments, and recent studies with dyslexic children across languages reveal a relationship between auditory temporal processing and sensitivity to rhythmic timing and speech rhythm. As rhythm is explicit in music, musical training might have a beneficial effect on the auditory perception of acoustic cues to rhythm in dyslexia. Here we took advantage of the presence of musicians with and without dyslexia in musical conservatoires, comparing their auditory temporal processing abilities with those of dyslexic non-musicians matched for cognitive ability. Musicians with dyslexia showed equivalent auditory sensitivity to musicians without dyslexia and also showed equivalent rhythm perception. The data support the view that extensive rhythmic experience initiated during childhood (here in the form of music training) can affect basic auditory processing skills which are found to be deficient in individuals with dyslexia.

  19. The role of temporal coherence in auditory stream segregation

    DEFF Research Database (Denmark)

    Christiansen, Simon Krogholt

    The ability to perceptually segregate concurrent sound sources and focus one’s attention on a single source at a time is essential for the ability to use acoustic information. While perceptual experiments have determined a range of acoustic cues that help facilitate auditory stream segregation...... of auditory processing, the role of auditory preprocessing and temporal coherence in auditory stream formation was evaluated. The computational model presented in this study assumes that auditory stream segregation occurs when sounds stimulate non-overlapping neural populations in a temporally incoherent...... on the stream segregation process was analysed. The model analysis showed that auditory frequency selectivity and physiological forward masking play a significant role in stream segregation based on frequency separation and tone rate. Secondly, the model analysis suggested that neural adaptation...

  20. Randomized $\\Delta$-Edge-Coloring via Quaternion of Complex Colors

    OpenAIRE

    Lee, Tony T.; Wan, Yujie; Guan, Hao

    2011-01-01

    This paper explores the application of a new algebraic method of color exchanges to the edge coloring of simple graphs. Vizing's theorem states that the edge coloring of a simple graph $G$ requires either $\\Delta$ or $\\Delta+1$ colors, where $\\Delta$ is the maximum vertex degree of $G$. Holyer proved that it is {\\bf NP}-complete to decide whether $G$ is $\\Delta$-edge-colorable even for cubic graphs. By introducing the concept of complex colors, we show that the color-exchange operation follow...

  1. Perspectives on the design of musical auditory interfaces

    OpenAIRE

    Leplatre, G.; Brewster, S.A.

    1998-01-01

    This paper addresses the issue of music as a communication medium in auditory human-computer interfaces. So far, psychoacoustics has had a great influence on the development of auditory interfaces, directly and through music cognition. We suggest that a better understanding of the processes involved in the perception of actual musical excerpts should allow musical auditory interface designers to exploit the communicative potential of music. In this respect, we argue that the real advantage of...

  2. [Auditory guidance systems for the visually impaired people].

    Science.gov (United States)

    He, Jing; Nie, Min; Luo, Lan; Tong, Shanbao; Niu, Jinhai; Zhu, Yisheng

    2010-04-01

    Visually impaired people face many inconveniences because of the loss of vision. Therefore, scientists are trying to design various guidance systems for improving the lives of the blind. Based on sensory substitution, auditory guidance has become an interesting topic in the field of biomedical engineering. In this paper, we made a state-of-technique review of the auditory guidance system. Although there have been many technical challenges, the auditory guidance system would be a useful alternative for the visually impaired people.

  3. Time course of dynamic range adaptation in the auditory nerve

    OpenAIRE

    Wen, Bo; Wang, Grace I.; Dean, Isabel; Delgutte, Bertrand

    2012-01-01

    Auditory adaptation to sound-level statistics occurs as early as in the auditory nerve (AN), the first stage of neural auditory processing. In addition to firing rate adaptation characterized by a rate decrement dependent on previous spike activity, AN fibers show dynamic range adaptation, which is characterized by a shift of the rate-level function or dynamic range toward the most frequently occurring levels in a dynamic stimulus, thereby improving the precision of coding of the most common ...

  4. Using Facebook to Reach People Who Experience Auditory Hallucinations

    OpenAIRE

    Crosier, Benjamin Sage; Brian, Rachel Marie; Ben-Zeev, Dror

    2016-01-01

    Background Auditory hallucinations (eg, hearing voices) are relatively common and underreported false sensory experiences that may produce distress and impairment. A large proportion of those who experience auditory hallucinations go unidentified and untreated. Traditional engagement methods oftentimes fall short in reaching the diverse population of people who experience auditory hallucinations. Objective The objective of this proof-of-concept study was to examine the viability of leveraging...

  5. Speech Perception Within an Auditory Cognitive Science Framework

    OpenAIRE

    Holt, Lori L.; Lotto, Andrew J.

    2008-01-01

    The complexities of the acoustic speech signal pose many significant challenges for listeners. Although perceiving speech begins with auditory processing, investigation of speech perception has progressed mostly independently of study of the auditory system. Nevertheless, a growing body of evidence demonstrates that cross-fertilization between the two areas of research can be productive. We briefly describe research bridging the study of general auditory processing and speech perception, show...

  6. Effect of auditory training on the middle latency response in children with (central) auditory processing disorder.

    Science.gov (United States)

    Schochat, E; Musiek, F E; Alonso, R; Ogata, J

    2010-08-01

    The purpose of this study was to determine the middle latency response (MLR) characteristics (latency and amplitude) in children with (central) auditory processing disorder [(C)APD], categorized as such by their performance on the central auditory test battery, and the effects of these characteristics after auditory training. Thirty children with (C)APD, 8 to 14 years of age, were tested using the MLR-evoked potential. This group was then enrolled in an 8-week auditory training program and then retested at the completion of the program. A control group of 22 children without (C)APD, composed of relatives and acquaintances of those involved in the research, underwent the same testing at equal time intervals, but were not enrolled in the auditory training program. Before auditory training, MLR results for the (C)APD group exhibited lower C3-A1 and C3-A2 wave amplitudes in comparison to the control group [C3-A1, 0.84 microV (mean), 0.39 (SD--standard deviation) for the (C)APD group and 1.18 microV (mean), 0.65 (SD) for the control group; C3-A2, 0.69 microV (mean), 0.31 (SD) for the (C)APD group and 1.00 microV (mean), 0.46 (SD) for the control group]. After training, the MLR C3-A1 [1.59 microV (mean), 0.82 (SD)] and C3-A2 [1.24 microV (mean), 0.73 (SD)] wave amplitudes of the (C)APD group significantly increased, so that there was no longer a significant difference in MLR amplitude between (C)APD and control groups. These findings suggest progress in the use of electrophysiological measurements for the diagnosis and treatment of (C)APD.

  7. Effect of auditory training on the middle latency response in children with (central auditory processing disorder

    Directory of Open Access Journals (Sweden)

    E. Schochat

    2010-08-01

    Full Text Available The purpose of this study was to determine the middle latency response (MLR characteristics (latency and amplitude in children with (central auditory processing disorder [(CAPD], categorized as such by their performance on the central auditory test battery, and the effects of these characteristics after auditory training. Thirty children with (CAPD, 8 to 14 years of age, were tested using the MLR-evoked potential. This group was then enrolled in an 8-week auditory training program and then retested at the completion of the program. A control group of 22 children without (CAPD, composed of relatives and acquaintances of those involved in the research, underwent the same testing at equal time intervals, but were not enrolled in the auditory training program. Before auditory training, MLR results for the (CAPD group exhibited lower C3-A1 and C3-A2 wave amplitudes in comparison to the control group [C3-A1, 0.84 µV (mean, 0.39 (SD - standard deviation for the (CAPD group and 1.18 µV (mean, 0.65 (SD for the control group; C3-A2, 0.69 µV (mean, 0.31 (SD for the (CAPD group and 1.00 µV (mean, 0.46 (SD for the control group]. After training, the MLR C3-A1 [1.59 µV (mean, 0.82 (SD] and C3-A2 [1.24 µV (mean, 0.73 (SD] wave amplitudes of the (CAPD group significantly increased, so that there was no longer a significant difference in MLR amplitude between (CAPD and control groups. These findings suggest progress in the use of electrophysiological measurements for the diagnosis and treatment of (CAPD.

  8. Klinefelter syndrome has increased brain responses to auditory stimuli and motor output, but not to visual stimuli or Stroop adaptation

    Directory of Open Access Journals (Sweden)

    Mikkel Wallentin

    2016-01-01

    Full Text Available Klinefelter syndrome (47, XXY (KS is a genetic syndrome characterized by the presence of an extra X chromosome and low level of testosterone, resulting in a number of neurocognitive abnormalities, yet little is known about brain function. This study investigated the fMRI-BOLD response from KS relative to a group of Controls to basic motor, perceptual, executive and adaptation tasks. Participants (N: KS = 49; Controls = 49 responded to whether the words “GREEN” or “RED” were displayed in green or red (incongruent versus congruent colors. One of the colors was presented three times as often as the other, making it possible to study both congruency and adaptation effects independently. Auditory stimuli saying “GREEN” or “RED” had the same distribution, making it possible to study effects of perceptual modality as well as Frequency effects across modalities. We found that KS had an increased response to motor output in primary motor cortex and an increased response to auditory stimuli in auditory cortices, but no difference in primary visual cortices. KS displayed a diminished response to written visual stimuli in secondary visual regions near the Visual Word Form Area, consistent with the widespread dyslexia in the group. No neural differences were found in inhibitory control (Stroop or in adaptation to differences in stimulus frequencies. Across groups we found a strong positive correlation between age and BOLD response in the brain's motor network with no difference between groups. No effects of testosterone level or brain volume were found. In sum, the present findings suggest that auditory and motor systems in KS are selectively affected, perhaps as a compensatory strategy, and that this is not a systemic effect as it is not seen in the visual system.

  9. The constancy of physics.

    Science.gov (United States)

    Irvine, J. M.; Humphreys, R.

    Evidence restricting the secular variation of the coupling constants of nature is reviewed. The nature of "natural" units is discussed and possible forms of gravitational coupling examined. Particular attention is paid to data obtained from a study of the prehistoric natural reactor at Oklo and the restrictions which present day isotopic abundances place on interaction strengths and mass parameters during the era of primordial nucleosynthesis.

  10. Evaluation of peripheral compression and auditory nerve fiber intensity coding using auditory steady-state responses

    DEFF Research Database (Denmark)

    Encina Llamas, Gerard; M. Harte, James; Epp, Bastian

    2015-01-01

    . Evaluation of these properties provides information about the health state of the system. It has been shown that a loss of outer hair cells leads to a reduction in peripheral compression. It has also recently been shown in animal studies that noise over-exposure, producing temporary threshold shifts, can......The compressive nonlinearity of the auditory system is assumed to be an epiphenomenon of a healthy cochlea and, particularly, of outer-hair cell function. Another ability of the healthy auditory system is to enable communication in acoustical environments with high-level background noises...

  11. Sound objects – Auditory objects – Musical objects

    DEFF Research Database (Denmark)

    Hjortkjær, Jens

    2015-01-01

    The auditory system transforms patterns of sound energy into perceptual objects but the precise definition of an ‘auditory object’ is much debated. In the context of music listening, Pierre Schaeffer argued that ‘sound objects’ are the fundamental perceptual units in ‘musical objects......’. In this paper, I review recent neurocognitive research suggesting that the auditory system is sensitive to structural information about real-world objects. Instead of focusing solely on perceptual sound features as determinants of auditory objects, I propose that real-world object properties are inherent...

  12. Sound objects – Auditory objects – Musical objects

    DEFF Research Database (Denmark)

    Hjortkjær, Jens

    2016-01-01

    The auditory system transforms patterns of sound energy into perceptual objects but the precise definition of an ‘auditory object’ is much debated. In the context of music listening, Pierre Schaeffer argued that ‘sound objects’ are the fundamental perceptual units in ‘musical objects......’. In this paper, I review recent neurocognitive research suggesting that the auditory system is sensitive to structural information about real-world objects. Instead of focusing solely on perceptual sound features as determinants of auditory objects, I propose that real-world object properties are inherent...

  13. Extrinsic sound stimulations and development of periphery auditory synapses

    Institute of Scientific and Technical Information of China (English)

    Kun Hou; Shiming Yang; Ke Liu

    2015-01-01

    The development of auditory synapses is a key process for the maturation of hearing function. However, it is still on debate regarding whether the development of auditory synapses is dominated by acquired sound stimulations. In this review, we summarize relevant publications in recent decades to address this issue. Most reported data suggest that extrinsic sound stimulations do affect, but not govern the development of periphery auditory synapses. Overall, periphery auditory synapses develop and mature according to its intrinsic mechanism to build up the synaptic connections between sensory neurons and/or interneurons.

  14. Backbone colorings along perfect matchings

    NARCIS (Netherlands)

    Broersma, H.J.; Fujisawa, J.; Yoshimoto, K.

    2003-01-01

    Given a graph $G=(V,E)$ and a spanning subgraph $H$ of $G$ (the backbone of $G$), a backbone coloring for $G$ and $H$ is a proper vertex coloring $V\\rightarrow \\{1,2,\\ldots\\}$ of $G$ in which the colors assigned to adjacent vertices in $H$ differ by at least two. In a recent paper, backbone coloring

  15. Harmonious coloring of uniform hypergraphs

    OpenAIRE

    Bartłomiej Bosek; Sebastian Czerwiński; Jarosław Grytczuk; Paweł Rzążewski

    2016-01-01

    A \\emph{harmonious coloring} of a $k$-uniform hypergraph $H$ is a vertex coloring such that no two vertices in the same edge share the same color, and each $k$-element subset of colors appears on at most one edge. The \\emph{% harmonious number} $h(H)$ is the least number of colors needed for such a coloring. %These notions arose as a natural extension of a widely studied %topic of harmonious coloring of simple graphs. We prove that $k$-uniform hypergraphs of bounded maxim...

  16. Artificial color perception using microwaves

    CERN Document Server

    Choudhury, Debesh

    2013-01-01

    We report the feasibility of artificial color perception under microwave illumination using a standard microwave source and an antenna. We have sensed transmitted microwave power through color objects and have distinguished the colors by analyzing the sensed transmitted power. Experiments are carried out using a Gunn diode as the microwave source, some colored liquids as the objects and a microwave diode as the detector. Results are presented which open up an unusual but new way of perceiving colors using microwaves.

  17. The Role of Auditory and Kinaesthetic Feedback Mechanisms on Phonatory Stability in Children

    OpenAIRE

    Rathna Kumar, S. B.; Azeem, Suhail; Choudhary, Abhishek Kumar; Prakash, S. G. R.

    2012-01-01

    Auditory feedback plays an important role in phonatory control. When auditory feedback is disrupted, various changes are observed in vocal motor control. Vocal intensity and fundamental frequency (F0) levels tend to increase in response to auditory masking. Because of the close reflexive links between the auditory and phonatory systems, it is likely that phonatory stability may be disrupted when auditory feedback is disrupted or altered. However, studies on phonatory stability under auditory ...

  18. Precision of Synesthetic Color Matching Resembles That for Recollected Colors Rather than Physical Colors

    Science.gov (United States)

    Arnold, Derek H.; Wegener, Signy V.; Brown, Francesca; Mattingley, Jason B.

    2012-01-01

    Grapheme-color synesthesia is an atypical condition in which individuals experience sensations of color when reading printed graphemes such as letters and digits. For some grapheme-color synesthetes, seeing a printed grapheme triggers a sensation of color, but "hearing" the name of a grapheme does not. This dissociation allowed us to compare the…

  19. Color Memory of University Students: Influence of Color Experience and Color Characteristic

    Science.gov (United States)

    Bynum, Carlisle; Epps, Helen H.; Kaya, Naz

    2006-01-01

    The ability to select a previously viewed color specimen from an array of specimens that differ in hue, value, or chroma varies among individuals, and may be related to one's basic color discrimination ability or to prior experience with color. This study investigated short-term color memory of 40 college students, 20 of whom were interior design…

  20. The color "fruit": object memories defined by color.

    Science.gov (United States)

    Lewis, David E; Pearson, Joel; Khuu, Sieu K

    2013-01-01

    Most fruits and other highly color-diagnostic objects have color as a central aspect of their identity, which can facilitate detection and visual recognition. It has been theorized that there may be a large amount of overlap between the neural representations of these objects and processing involved in color perception. In accordance with this theory we sought to determine if the recognition of highly color diagnostic fruit objects could be facilitated by the visual presentation of their known color associates. In two experiments we show that color associate priming is possible, but contingent upon multiple factors. Color priming was found to be maximally effective for the most highly color diagnostic fruits, when low spatial-frequency information was present in the image, and when determination of the object's specific identity, not merely its category, was required. These data illustrate the importance of color for determining the identity of certain objects, and support the theory that object knowledge involves sensory specific systems.

  1. Color control of the multi-color printing device

    Institute of Scientific and Technical Information of China (English)

    WANG Xiao-hua; XIU Xiao-jie; ZHU Wen-hua; TANG Hong-jun

    2006-01-01

    Conventional color-printing systems often use inks of three hues, such as CMY, CMYK and CMYKLcLm, but in order to obtain more realistic color reproductions, the ink set of more than three hues has been adopted by some color-printing systems. It is difficult, however, to model the composed color with the multiple inks when the number of the output ink hues exceeds three due to the none-unique mapping between the color spaces of the CIE Lab and the multi-color printing device. In this paper, we propose a fine color-printing method for multi-color printing device with the ink set of more than three hues. The proposed approach has good color expression ability and provides fine control of the printed color. By dividing the output color space into several subspaces, our method allows one-to-one mapping between the standard color space and the multi-color output color space. It has been proved effective when applied to the digital inkjet printer-Mutoh8000.

  2. Training in rapid auditory processing ameliorates auditory comprehension in aphasic patients: a randomized controlled pilot study.

    Science.gov (United States)

    Szelag, Elzbieta; Lewandowska, Monika; Wolak, Tomasz; Seniow, Joanna; Poniatowska, Renata; Pöppel, Ernst; Szymaszek, Aneta

    2014-03-15

    Experimental studies have often reported close associations between rapid auditory processing and language competency. The present study was aimed at improving auditory comprehension in aphasic patients following specific training in the perception of temporal order (TO) of events. We tested 18 aphasic patients showing both comprehension and TO perception deficits. Auditory comprehension was assessed by the Token Test, phonemic awareness and Voice-Onset-Time Test. The TO perception was assessed using auditory Temporal-Order-Threshold, defined as the shortest interval between two consecutive stimuli, necessary to report correctly their before-after relation. Aphasic patients participated in eight 45-minute sessions of either specific temporal training (TT, n=11) aimed to improve sequencing abilities, or control non-temporal training (NT, n=7) focussed on volume discrimination. The TT yielded improved TO perception; moreover, a transfer of improvement was observed from the time domain to the language domain, which was untrained during the training. The NT did not improve either the TO perception or comprehension in any language test. These results are in agreement with previous literature studies which proved ameliorated language competency following the TT in language-learning-impaired or dyslexic children. Our results indicated for the first time such benefits also in aphasic patients. PMID:24388435

  3. Auditory excitation patterns : the significance of the pulsation threshold method for the measurement of auditory nonlinearity

    NARCIS (Netherlands)

    H. Verschuure (Hans)

    1978-01-01

    textabstractThe auditory system is the toto[ of organs that translates an acoustical signal into the perception of a sound. An acoustic signal is a vibration. It is decribed by physical parameters. The perception of sound is the awareness of a signal being present and the attribution of certain qual

  4. Future of color

    Science.gov (United States)

    Ladson, Jack A.; Turner, Laraine B.; Green-Armytage, Paul; Hunt, Robert W. G.

    2002-06-01

    We live in a world in which styles and technologies are nearly the same from place to place, but change daily. This changing global culture is unprecedented, and reinforced by emerging new technologies that affect us all. The Future of Color, examines new technologies, how they will affect the selection and promulgation of color in the near future, and their impact upon us. We examine this topic from many perspectives - technological, business and commercial. Most importantly, as we understand how our world is emerging, we can position ourselves strategically for tomorrow.

  5. Plate Full of Color

    Centers for Disease Control (CDC) Podcasts

    2008-08-04

    The Eagle Books are a series of four books that are brought to life by wise animal characters - Mr. Eagle, Miss Rabbit, and Coyote - who engage Rain That Dances and his young friends in the joy of physical activity, eating healthy foods, and learning from their elders about health and diabetes prevention. Plate Full of Color teaches the value of eating a variety of colorful and healthy foods.  Created: 8/4/2008 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 8/5/2008.

  6. The Colors of Saturn

    Science.gov (United States)

    DeVogel, Kayla; Chanover, Nancy; Thelen, Alexander

    2015-11-01

    Very little is known about the coloring agents, or chromophores, that color the clouds of Saturn’s belts and zones. Although the clouds of Saturn are more muted in their coloration and do not exhibit the more striking variations seen among Jupiter’s belts, zones, and cyclonic storm features, the physical processes that render Saturn’s clouds a yellowish hue are likely similar to those at work on Jupiter. Thus, a comprehensive color study that includes both Jupiter and Saturn is warranted to advance our understanding of chromophores in the giant planet atmospheres. Here we report on our efforts to characterize the colors of Saturn’s clouds.This study involves the analysis of two imaging data sets: those from Cassini’s Imaging Science Subsystem (ISS), and Wide Field Planetary Camera 2 images taken with the Hubble Space Telescope (HST). The HST data were acquired in 1994, 1998, 2002 and 2004 using eleven different filters spanning 255-973 nm. After the images were photometrically and geometrically calibrated, we used them to create low resolution spectra for six different latitude regions: the Equatorial Zone, the Equatorial Belt, the South Equatorial Belt, the South Temperate Zone, the South Temperate Belt and the South South Temperate Belt. The Cassini ISS images were acquired in 2004 and 2011 using twelve different filters spanning 258-938 nm, and corresponding low resolution spectra of the same latitude regions were generated using the ISS images. We compare these low resolution spectra to Saturn’s full-disk spectrum (Karkoschka, E., 1994, Icarus 111, 174) to examine colors of discrete latitudes versus the full-disk spectrum of Saturn. The extensive temporal coverage afforded by the combination of the HST and ISS images will enable us to explore possible seasonal variations in Saturn’s cloud colors. Finally, we examine the color evolution of the major 2011 storm on Saturn using the ISS data.This work was supported by the Discovery Scholars Program in

  7. QCD: color or glow

    International Nuclear Information System (INIS)

    The some of motivations for color and the numerous qualitative successes of QCD are presented. Non-leading higher order contributions to the (x, Q2)-dependence of scaling violations of non-singlet and singlet structure functions are discussed, especially non-perturbative correction to deep inelastic processes such as higher twist contributions. Finally the topic of how to account theoretically for the existence of free fractionally charged particles by concentrating mainly on spontaneously breaking SU(3) color is presented. (M.F.W.)

  8. Tool for the verification of geometrical parameters and constancy of image quality in radiology equipment; Herramienta para la verificacion de parametros geometricos y constancia de calidad de imagen en equipos de radiodiagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Mayo, P.; Verdu Martin, G.; Rodenas Escriba, F.; Marin Peinado, B.; Camapyo Esteban Nogueira, J. M.; Diez Domingo, S.; Villaescusa Blanca, J. I.; Hernando Gonzalez, I.; Ruiz Manzano, P.; Rivas Ballarin, M. A.; Melcho Iniguez, M.; Asensio Martinez, M. I.

    2013-07-01

    This paper presents the application of an innovative tool developed for the detailed quality control of diagnostic equipment. We have tried to validate such a tool for verification of geometrical parameters and the evaluation of the constancy of the image quality in radiology equipment, evaluating their usefulness by various services of Radio physics and radiation protection of different hospitals. (Author)

  9. A critical period for auditory thalamocortical connectivity

    DEFF Research Database (Denmark)

    Rinaldi Barkat, Tania; Polley, Daniel B; Hensch, Takao K

    2011-01-01

    connectivity by in vivo recordings and day-by-day voltage-sensitive dye imaging in an acute brain slice preparation. Passive tone-rearing modified response strength and topography in mouse primary auditory cortex (A1) during a brief, 3-d window, but did not alter tonotopic maps in the thalamus. Gene......-targeted deletion of a forebrain-specific cell-adhesion molecule (Icam5) accelerated plasticity in this critical period. Consistent with its normal role of slowing spinogenesis, loss of Icam5 induced precocious stubby spine maturation on pyramidal cell dendrites in neocortical layer 4 (L4), identifying a primary...

  10. CAVERNOUS HEMANGIOMA OF THE INTERNAL AUDITORY CANAL

    Directory of Open Access Journals (Sweden)

    Mohammad Hossein Hekmatara

    1993-06-01

    Full Text Available Cavernous hemangioma is a rare benign tumor of the internal auditory canal (IAC of which fourteen cases have been reported so far."nTinnitus and progressive sensorineural hearing loss (SNHL are the chief complaints of the patients. Audiological and radiological planes, CTScan, and magnetic resonance image (MRI studies are helpful in diagnosis. The only choice of treatment is surgery with elective transmastoid trans¬labyrinthine approach. And if tumor is very large, the method of choice will be retrosigmoid approach.

  11. INFLUENCE ON VESTIBULAR FUNCTION BY AUDITORY NEUROPATHY

    Institute of Scientific and Technical Information of China (English)

    WANG Jingmiao; JIANG Xinxia; SHAN Chunguang

    2013-01-01

    Objective The main purpose of the present study was to describe the vestibular function in patients with auditory neuropathy (AN), and to assess their ability to maintain balance. Methods Vestibular function tests were performed on 32 patients with AN and 36 normal subjects including electronystagmopraphy(ENG) and static postrography(SPG). The results from the two groups were compared. Results Equilibrium function in patients with AN, was abnormal, compared to normal subjects. Conclusion Vestibular function tests, espe-cially static postrography, should be performed on patients with AN.

  12. Left auditory cortex gamma synchronization and auditory hallucination symptoms in schizophrenia

    Directory of Open Access Journals (Sweden)

    Shenton Martha E

    2009-07-01

    Full Text Available Abstract Background Oscillatory electroencephalogram (EEG abnormalities may reflect neural circuit dysfunction in neuropsychiatric disorders. Previously we have found positive correlations between the phase synchronization of beta and gamma oscillations and hallucination symptoms in schizophrenia patients. These findings suggest that the propensity for hallucinations is associated with an increased tendency for neural circuits in sensory cortex to enter states of oscillatory synchrony. Here we tested this hypothesis by examining whether the 40 Hz auditory steady-state response (ASSR generated in the left primary auditory cortex is positively correlated with auditory hallucination symptoms in schizophrenia. We also examined whether the 40 Hz ASSR deficit in schizophrenia was associated with cross-frequency interactions. Sixteen healthy control subjects (HC and 18 chronic schizophrenia patients (SZ listened to 40 Hz binaural click trains. The EEG was recorded from 60 electrodes and average-referenced offline. A 5-dipole model was fit from the HC grand average ASSR, with 2 pairs of superior temporal dipoles and a deep midline dipole. Time-frequency decomposition was performed on the scalp EEG and source data. Results Phase locking factor (PLF and evoked power were reduced in SZ at fronto-central electrodes, replicating prior findings. PLF was reduced in SZ for non-homologous right and left hemisphere sources. Left hemisphere source PLF in SZ was positively correlated with auditory hallucination symptoms, and was modulated by delta phase. Furthermore, the correlations between source evoked power and PLF found in HC was reduced in SZ for the LH sources. Conclusion These findings suggest that differential neural circuit abnormalities may be present in the left and right auditory cortices in schizophrenia. In addition, they provide further support for the hypothesis that hallucinations are related to cortical hyperexcitability, which is manifested by

  13. From ear to hand: the role of the auditory-motor loop in pointing to an auditory source

    Science.gov (United States)

    Boyer, Eric O.; Babayan, Bénédicte M.; Bevilacqua, Frédéric; Noisternig, Markus; Warusfel, Olivier; Roby-Brami, Agnes; Hanneton, Sylvain; Viaud-Delmon, Isabelle

    2013-01-01

    Studies of the nature of the neural mechanisms involved in goal-directed movements tend to concentrate on the role of vision. We present here an attempt to address the mechanisms whereby an auditory input is transformed into a motor command. The spatial and temporal organization of hand movements were studied in normal human subjects as they pointed toward unseen auditory targets located in a horizontal plane in front of them. Positions and movements of the hand were measured by a six infrared camera tracking system. In one condition, we assessed the role of auditory information about target position in correcting the trajectory of the hand. To accomplish this, the duration of the target presentation was varied. In another condition, subjects received continuous auditory feedback of their hand movement while pointing to the auditory targets. Online auditory control of the direction of pointing movements was assessed by evaluating how subjects reacted to shifts in heard hand position. Localization errors were exacerbated by short duration of target presentation but not modified by auditory feedback of hand position. Long duration of target presentation gave rise to a higher level of accuracy and was accompanied by early automatic head orienting movements consistently related to target direction. These results highlight the efficiency of auditory feedback processing in online motor control and suggest that the auditory system takes advantages of dynamic changes of the acoustic cues due to changes in head orientation in order to process online motor control. How to design an informative acoustic feedback needs to be carefully studied to demonstrate that auditory feedback of the hand could assist the monitoring of movements directed at objects in auditory space. PMID:23626532

  14. Auditory perceptual simulation: Simulating speech rates or accents?

    Science.gov (United States)

    Zhou, Peiyun; Christianson, Kiel

    2016-07-01

    When readers engage in Auditory Perceptual Simulation (APS) during silent reading, they mentally simulate characteristics of voices attributed to a particular speaker or a character depicted in the text. Previous research found that auditory perceptual simulation of a faster native English speaker during silent reading led to shorter reading times that auditory perceptual simulation of a slower non-native English speaker. Yet, it was uncertain whether this difference was triggered by the different speech rates of the speakers, or by the difficulty of simulating an unfamiliar accent. The current study investigates this question by comparing faster Indian-English speech and slower American-English speech in the auditory perceptual simulation paradigm. Analyses of reading times of individual words and the full sentence reveal that the auditory perceptual simulation effect again modulated reading rate, and auditory perceptual simulation of the faster Indian-English speech led to faster reading rates compared to auditory perceptual simulation of the slower American-English speech. The comparison between this experiment and the data from Zhou and Christianson (2016) demonstrate further that the "speakers'" speech rates, rather than the difficulty of simulating a non-native accent, is the primary mechanism underlying auditory perceptual simulation effects. PMID:27177077

  15. Auditory and visual spatial impression: Recent studies of three auditoria

    Science.gov (United States)

    Nguyen, Andy; Cabrera, Densil

    2004-10-01

    Auditory spatial impression is widely studied for its contribution to auditorium acoustical quality. By contrast, visual spatial impression in auditoria has received relatively little attention in formal studies. This paper reports results from a series of experiments investigating the auditory and visual spatial impression of concert auditoria. For auditory stimuli, a fragment of an anechoic recording of orchestral music was convolved with calibrated binaural impulse responses, which had been made with the dummy head microphone at a wide range of positions in three auditoria and the sound source on the stage. For visual stimuli, greyscale photographs were used, taken at the same positions in the three auditoria, with a visual target on the stage. Subjective experiments were conducted with auditory stimuli alone, visual stimuli alone, and visual and auditory stimuli combined. In these experiments, subjects rated apparent source width, listener envelopment, intimacy and source distance (auditory stimuli), and spaciousness, envelopment, stage dominance, intimacy and target distance (visual stimuli). Results show target distance to be of primary importance in auditory and visual spatial impression-thereby providing a basis for covariance between some attributes of auditory and visual spatial impression. Nevertheless, some attributes of spatial impression diverge between the senses.

  16. Auditory Processing Theories of Language Disorders: Past, Present, and Future

    Science.gov (United States)

    Miller, Carol A.

    2011-01-01

    Purpose: The purpose of this article is to provide information that will assist readers in understanding and interpreting research literature on the role of auditory processing in communication disorders. Method: A narrative review was used to summarize and synthesize the literature on auditory processing deficits in children with auditory…

  17. Quantification of the auditory startle reflex in children

    NARCIS (Netherlands)

    Bakker, Mirte J.; Boer, Frits; van der Meer, Johan N.; Koelman, Johannes H. T. M.; Boeree, Thijs; Bour, Lo; Tijssen, Marina A. J.

    2009-01-01

    Objective: To find an adequate tool to assess the auditory startle reflex (ASR) in children. Methods: We investigated the effect of stimulus repetition, gender and age on several quantifications of the ASR. ASR's were elicited by eight consecutive auditory stimuli in 27 healthy children. Electromyog

  18. Cortical Auditory Evoked Potentials in Unsuccessful Cochlear Implant Users

    Science.gov (United States)

    Munivrana, Boska; Mildner, Vesna

    2013-01-01

    In some cochlear implant users, success is not achieved in spite of optimal clinical factors (including age at implantation, duration of rehabilitation and post-implant hearing level), which may be attributed to disorders at higher levels of the auditory pathway. We used cortical auditory evoked potentials to investigate the ability to perceive…

  19. Effect of Auditory Interference on Memory of Haptic Perceptions.

    Science.gov (United States)

    Anater, Paul F.

    1980-01-01

    The effect of auditory interference on the processing of haptic information by 61 visually impaired students (8 to 20 years old) was the focus of the research described in this article. It was assumed that as the auditory interference approximated the verbalized activity of the haptic task, accuracy of recall would decline. (Author)

  20. A Pilot Study of Auditory Integration Training in Autism.

    Science.gov (United States)

    Rimland, Bernard; Edelson, Stephen M.

    1995-01-01

    The effectiveness of Auditory Integration Training (AIT) in 8 autistic individuals (ages 4-21) was evaluated using repeated multiple criteria assessment over a 3-month period. Compared to matched controls, subjects' scores improved on the Aberrant Behavior Checklist and Fisher's Auditory Problems Checklist. AIT did not decrease sound sensitivity.…

  1. Statistical representation of sound textures in the impaired auditory system

    DEFF Research Database (Denmark)

    McWalter, Richard Ian; Dau, Torsten

    2015-01-01

    homogenous sounds such as rain, birds, or fire. It has been suggested that sound texture perception is mediated by time-averaged statistics measured from early auditory representations (McDermott et al., 2013). Changes to early auditory processing, such as broader “peripheral” filters or reduced compression...

  2. Functional sex differences in human primary auditory cortex

    NARCIS (Netherlands)

    Ruytjens, Liesbet; Georgiadis, Janniko R.; Holstege, Gert; Wit, Hero P.; Albers, Frans W. J.; Willemsen, Antoon T. M.

    2007-01-01

    Background We used PET to study cortical activation during auditory stimulation and found sex differences in the human primary auditory cortex (PAC). Regional cerebral blood flow (rCBF) was measured in 10 male and 10 female volunteers while listening to sounds (music or white noise) and during a bas

  3. Impact of Educational Level on Performance on Auditory Processing Tests.

    Science.gov (United States)

    Murphy, Cristina F B; Rabelo, Camila M; Silagi, Marcela L; Mansur, Letícia L; Schochat, Eliane

    2016-01-01

    Research has demonstrated that a higher level of education is associated with better performance on cognitive tests among middle-aged and elderly people. However, the effects of education on auditory processing skills have not yet been evaluated. Previous demonstrations of sensory-cognitive interactions in the aging process indicate the potential importance of this topic. Therefore, the primary purpose of this study was to investigate the performance of middle-aged and elderly people with different levels of formal education on auditory processing tests. A total of 177 adults with no evidence of cognitive, psychological or neurological conditions took part in the research. The participants completed a series of auditory assessments, including dichotic digit, frequency pattern and speech-in-noise tests. A working memory test was also performed to investigate the extent to which auditory processing and cognitive performance were associated. The results demonstrated positive but weak correlations between years of schooling and performance on all of the tests applied. The factor "years of schooling" was also one of the best predictors of frequency pattern and speech-in-noise test performance. Additionally, performance on the working memory, frequency pattern and dichotic digit tests was also correlated, suggesting that the influence of educational level on auditory processing performance might be associated with the cognitive demand of the auditory processing tests rather than auditory sensory aspects itself. Longitudinal research is required to investigate the causal relationship between educational level and auditory processing skills.

  4. Impact of Educational Level on Performance on Auditory Processing Tests.

    Science.gov (United States)

    Murphy, Cristina F B; Rabelo, Camila M; Silagi, Marcela L; Mansur, Letícia L; Schochat, Eliane

    2016-01-01

    Research has demonstrated that a higher level of education is associated with better performance on cognitive tests among middle-aged and elderly people. However, the effects of education on auditory processing skills have not yet been evaluated. Previous demonstrations of sensory-cognitive interactions in the aging process indicate the potential importance of this topic. Therefore, the primary purpose of this study was to investigate the performance of middle-aged and elderly people with different levels of formal education on auditory processing tests. A total of 177 adults with no evidence of cognitive, psychological or neurological conditions took part in the research. The participants completed a series of auditory assessments, including dichotic digit, frequency pattern and speech-in-noise tests. A working memory test was also performed to investigate the extent to which auditory processing and cognitive performance were associated. The results demonstrated positive but weak correlations between years of schooling and performance on all of the tests applied. The factor "years of schooling" was also one of the best predictors of frequency pattern and speech-in-noise test performance. Additionally, performance on the working memory, frequency pattern and dichotic digit tests was also correlated, suggesting that the influence of educational level on auditory processing performance might be associated with the cognitive demand of the auditory processing tests rather than auditory sensory aspects itself. Longitudinal research is required to investigate the causal relationship between educational level and auditory processing skills. PMID:27013958

  5. Auditory Deprivation and Early Conductive Hearing Loss from Otitis Media.

    Science.gov (United States)

    Gunnarson, Adele D.; And Others

    1990-01-01

    This article reviews auditory deprivation effects on anatomy, physiology, and behavior in animals and discusses the sequelae of otitis media with effusion (OME) in children. Focused on are central auditory processing disorders associated with early fluctuating hearing loss from OME. (DB)

  6. Tinnitus intensity dependent gamma oscillations of the contralateral auditory cortex.

    Directory of Open Access Journals (Sweden)

    Elsa van der Loo

    Full Text Available BACKGROUND: Non-pulsatile tinnitus is considered a subjective auditory phantom phenomenon present in 10 to 15% of the population. Tinnitus as a phantom phenomenon is related to hyperactivity and reorganization of the auditory cortex. Magnetoencephalography studies demonstrate a correlation between gamma band activity in the contralateral auditory cortex and the presence of tinnitus. The present study aims to investigate the relation between objective gamma-band activity in the contralateral auditory cortex and subjective tinnitus loudness scores. METHODS AND FINDINGS: In unilateral tinnitus patients (N = 15; 10 right, 5 left source analysis of resting state electroencephalographic gamma band oscillations shows a strong positive correlation with Visual Analogue Scale loudness scores in the contralateral auditory cortex (max r = 0.73, p<0.05. CONCLUSION: Auditory phantom percepts thus show similar sound level dependent activation of the contralateral auditory cortex as observed in normal audition. In view of recent consciousness models and tinnitus network models these results suggest tinnitus loudness is coded by gamma band activity in the contralateral auditory cortex but might not, by itself, be responsible for tinnitus perception.

  7. Auditory Processing Learning Disability, Suicidal Ideation, and Transformational Faith

    Science.gov (United States)

    Bailey, Frank S.; Yocum, Russell G.

    2015-01-01

    The purpose of this personal experience as a narrative investigation is to describe how an auditory processing learning disability exacerbated--and how spirituality and religiosity relieved--suicidal ideation, through the lived experiences of an individual born and raised in the United States. The study addresses: (a) how an auditory processing…

  8. Loudspeaker-based room auralization in auditory perception research

    DEFF Research Database (Denmark)

    Buchholz, Jörg; Favrot, Sylvain Emmanuel

    2010-01-01

    , and aided-impaired auditory system in realistic environments and (ii) a framework to evaluate the effect of different room modeling and auralisation methods on auditory perception. The applicability of such environment is demonstrated using different objective room acoustic measures. Different experimental...... results are presented, including measures of distance perception and the effect of early reflections on speech intelligibility....

  9. Modeling auditory evoked brainstem responses to transient stimuli

    DEFF Research Database (Denmark)

    Rønne, Filip Munch; Dau, Torsten; Harte, James;

    2012-01-01

    A quantitative model is presented that describes the formation of auditory brainstem responses (ABR) to tone pulses, clicks and rising chirps as a function of stimulation level. The model computes the convolution of the instantaneous discharge rates using the “humanized” nonlinear auditory-nerve ...

  10. Subdividing the beat: auditory and motor contributions to synchronization

    NARCIS (Netherlands)

    Loehr, J.D.; Palmer, C.

    2009-01-01

    THE CURRENT STUDY EXAMINED HOW AUDITORY AND kinematic information influenced pianists' ability to synchronize musical sequences with a metronome. Pianists performed melodies in which quarter-note beats were subdivided by intervening eighth notes that resulted from auditory information (heard tones),

  11. Deactivation of the Parahippocampal Gyrus Preceding Auditory Hallucinations in Schizophrenia

    NARCIS (Netherlands)

    Diederen, Kelly M. J.; Neggers, Sebastiaan F. W.; Daalman, Kirstin; Blom, Jan Dirk; Goekoop, Rutger; Kahn, Rene S.; Sommer, Iris E. C.

    2010-01-01

    Objective: Activation in a network of language-related regions has been reported during auditory verbal hallucinations. It remains unclear, however, how this activation is triggered. Identifying brain regions that show significant signal changes preceding auditory hallucinations might reveal the ori

  12. Auditory feedback perturbation in children with developmental speech disorders

    NARCIS (Netherlands)

    Terband, H.R.; van Brenk, F.J.; van Doornik-van der Zee, J.C.

    2014-01-01

    Background/purpose: Several studies indicate a close relation between auditory and speech motor functions in children with speech sound disorders (SSD). The aim of this study was to investigate the ability to compensate and adapt for perturbed auditory feedback in children with SSD compared to age-m

  13. Comparison of auditory hallucinations across different disorders and syndromes

    NARCIS (Netherlands)

    Sommer, Iris E. C.; Koops, Sanne; Blom, Jan Dirk

    2012-01-01

    Auditory hallucinations can be experienced in the context of many different disorders and syndromes. The differential diagnosis basically rests on the presence or absence of accompanying symptoms. In terms of clinical relevance, the most important distinction to be made is between auditory hallucina

  14. Auditory-Visual Transfer in Four-Month-Old Infants.

    Science.gov (United States)

    Mendelson, Morton J.; Ferland, Mark B.

    1982-01-01

    Twenty-seven 4-month-old infants heard a repetitive auditory rhythm, then viewed silent film of puppet opening/closing its mouth, either in the familiar rhythm or a novel rhythm. Results showed infants exposed to the novel condition watched the film longer than infants shown the familiar condition, providing evidence for auditory-visual transfer…

  15. A Time-Frequency Auditory Model Using Wavelet Packets

    DEFF Research Database (Denmark)

    Agerkvist, Finn

    1996-01-01

    A time-frequency auditory model is presented. The model uses the wavelet packet analysis as the preprocessor. The auditory filters are modelled by the rounded exponential filters, and the excitation is smoothed by a window function. By comparing time-frequency excitation patterns it is shown...

  16. Auditory perceptual simulation: Simulating speech rates or accents?

    Science.gov (United States)

    Zhou, Peiyun; Christianson, Kiel

    2016-07-01

    When readers engage in Auditory Perceptual Simulation (APS) during silent reading, they mentally simulate characteristics of voices attributed to a particular speaker or a character depicted in the text. Previous research found that auditory perceptual simulation of a faster native English speaker during silent reading led to shorter reading times that auditory perceptual simulation of a slower non-native English speaker. Yet, it was uncertain whether this difference was triggered by the different speech rates of the speakers, or by the difficulty of simulating an unfamiliar accent. The current study investigates this question by comparing faster Indian-English speech and slower American-English speech in the auditory perceptual simulation paradigm. Analyses of reading times of individual words and the full sentence reveal that the auditory perceptual simulation effect again modulated reading rate, and auditory perceptual simulation of the faster Indian-English speech led to faster reading rates compared to auditory perceptual simulation of the slower American-English speech. The comparison between this experiment and the data from Zhou and Christianson (2016) demonstrate further that the "speakers'" speech rates, rather than the difficulty of simulating a non-native accent, is the primary mechanism underlying auditory perceptual simulation effects.

  17. Auditory Dysfunction and Its Communicative Impact in the Classroom.

    Science.gov (United States)

    Friedrich, Brad W.

    1982-01-01

    The origins and nature of auditory dysfunction in school age children and the role of the audiologist in the evaluation of the learning disabled child are reviewed. Specific structures and mechanisms responsible for the reception and perception of auditory signals are specified. (Author/SEW)

  18. Preparation and Culture of Chicken Auditory Brainstem Slices

    OpenAIRE

    Sanchez, Jason T.; Seidl, Armin H.; Rubel, Edwin W.; Barria, Andres

    2011-01-01

    The chicken auditory brainstem is a well-established model system that has been widely used to study the anatomy and physiology of auditory processing at discreet periods of development 1-4 as well as mechanisms for temporal coding in the central nervous system 5-7.

  19. Auditory signal design for automatic number plate recognition system

    NARCIS (Netherlands)

    Heydra, C.G.; Jansen, R.J.; Van Egmond, R.

    2014-01-01

    This paper focuses on the design of an auditory signal for the Automatic Number Plate Recognition system of Dutch national police. The auditory signal is designed to alert police officers of suspicious cars in their proximity, communicating priority level and location of the suspicious car and takin

  20. Overview of Central Auditory Processing Deficits in Older Adults.

    Science.gov (United States)

    Atcherson, Samuel R; Nagaraj, Naveen K; Kennett, Sarah E W; Levisee, Meredith

    2015-08-01

    Although there are many reported age-related declines in the human body, the notion that a central auditory processing deficit exists in older adults has not always been clear. Hearing loss and both structural and functional central nervous system changes with advancing age are contributors to how we listen, hear, and process auditory information. Even older adults with normal or near normal hearing sensitivity may exhibit age-related central auditory processing deficits as measured behaviorally and/or electrophysiologically. The purpose of this article is to provide an overview of assessment and rehabilitative approaches for central auditory processing deficits in older adults. It is hoped that the outcome of the information presented here will help clinicians with older adult patients who do not exhibit the typical auditory processing behaviors exhibited by others at the same age and with comparable hearing sensitivity all in the absence of other health-related conditions. PMID:27516715

  1. Colored Contact Lens Dangers

    Medline Plus

    Full Text Available ... contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are considering ... new treatment option. The U.S. Food and Drug Administration (FDA) has approved corneal collagen cross-linking (CXL) ...

  2. Transparency and imaginary colors

    NARCIS (Netherlands)

    Richards, W.; Koenderink, J.J.; Van Doorn, A.

    2009-01-01

    Unlike the Metelli monochrome transparencies, when overlays and their backgrounds have chromatic content, the inferred surface colors may not always be physically realizable, and are in some sense “imaginary.” In these cases, the inferred chromatic transmittance or reflectance of the overlay lies ou

  3. Dinosaurs' True Colors

    Institute of Scientific and Technical Information of China (English)

    TANG YUANKAI

    2010-01-01

    @@ On March 10,the Beijing Museum of Natural History(BMNH)announced scientists from China and abroad had decoded the full-body color patterns of a dinosaur,a small theropod named as anchiomis huxleyi,for the first time.

  4. Color appearance in stereoscopy

    Science.gov (United States)

    Gadia, Davide; Rizzi, Alessandro; Bonanomi, Cristian; Marini, Daniele; Galmonte, Alessandra; Agostini, Tiziano

    2011-03-01

    The relationship between color and lightness appearance and the perception of depth has been studied since a while in the field of perceptual psychology and psycho-physiology. It has been found that depth perception affects the final object color and lightness appearance. In the stereoscopy research field, many studies have been proposed on human physiological effects, considering e.g. geometry, motion sickness, etc., but few has been done considering lightness and color information. Goal of this paper is to realize some preliminar experiments in Virtual Reality in order to determine the effects of depth perception on object color and lightness appearance. We have created a virtual test scene with a simple 3D simultaneous contrast configuration. We have created three different versions of this scene, each with different choices of relative positions and apparent size of the objects. We have collected the perceptual responses of several users after the observation of the test scene in the Virtual Theater of the University of Milan, a VR immersive installation characterized by a semi-cylindrical screen that covers 120° of horizontal field of view from an observation distance of 3.5 m. We present a description of the experiments setup and procedure, and we discuss the obtained results.

  5. Comprehension of COLOR Metaphors

    Institute of Scientific and Technical Information of China (English)

    刘昱君

    2012-01-01

      本文试图通过对英汉颜色隐喻的比较研究,探讨隐喻的相似性及差异。%  In this thesis,I have attempted to discuss the similarities and differences of metaphor by making a comparative study of color metaphors in English and Chinese.

  6. Using Single Colors and Color Pairs to Communicate Basic Tastes

    Directory of Open Access Journals (Sweden)

    Andy T. Woods

    2016-07-01

    Full Text Available Recently, it has been demonstrated that people associate each of the basic tastes (e.g., sweet, sour, bitter, and salty with specific colors (e.g., red, green, black, and white. In the present study, we investigated whether pairs of colors (both associated with a particular taste or taste word would give rise to stronger associations relative to pairs of colors that were associated with different tastes. We replicate the findings of previous studies highlighting the existence of a robust crossmodal correspondence between individual colors and basic tastes. However, while there was evidence that pairs of colors could indeed communicate taste information more consistently than single colors, our participants took more than twice as long to match the color pairs with tastes than the single colors. Possible reasons for these results are discussed.

  7. Social Property of Colors and Translation of Color Words

    Institute of Scientific and Technical Information of China (English)

    曾慧彬

    2013-01-01

    The paper is about the social property of colors andtranslationofcolorwords.Colorsareveryimportantinour sociallife,accordingtothispaperwecanknowsomerelations aboutsocialandcolor.EspeciallyaboutthedifferencesofChinese and English color words. Through the differences, three basic translatingmethodsaregeneralized.

  8. Formal auditory training in adult hearing aid users

    Directory of Open Access Journals (Sweden)

    Daniela Gil

    2010-01-01

    Full Text Available INTRODUCTION: Individuals with sensorineural hearing loss are often able to regain some lost auditory function with the help of hearing aids. However, hearing aids are not able to overcome auditory distortions such as impaired frequency resolution and speech understanding in noisy environments. The coexistence of peripheral hearing loss and a central auditory deficit may contribute to patient dissatisfaction with amplification, even when audiological tests indicate nearly normal hearing thresholds. OBJECTIVE: This study was designed to validate the effects of a formal auditory training program in adult hearing aid users with mild to moderate sensorineural hearing loss. METHODS: Fourteen bilateral hearing aid users were divided into two groups: seven who received auditory training and seven who did not. The training program was designed to improve auditory closure, figure-to-ground for verbal and nonverbal sounds and temporal processing (frequency and duration of sounds. Pre- and post-training evaluations included measuring electrophysiological and behavioral auditory processing and administration of the Abbreviated Profile of Hearing Aid Benefit (APHAB self-report scale. RESULTS: The post-training evaluation of the experimental group demonstrated a statistically significant reduction in P3 latency, improved performance in some of the behavioral auditory processing tests and higher hearing aid benefit in noisy situations (p-value < 0,05. No changes were noted for the control group (p-value <0,05. CONCLUSION: The results demonstrated that auditory training in adult hearing aid users can lead to a reduction in P3 latency, improvements in sound localization, memory for nonverbal sounds in sequence, auditory closure, figure-to-ground for verbal sounds and greater benefits in reverberant and noisy environments.

  9. Hearing colors: an example of brain plasticity

    Science.gov (United States)

    Alfaro, Arantxa; Bernabeu, Ángela; Agulló, Carlos; Parra, Jaime; Fernández, Eduardo

    2015-01-01

    Sensory substitution devices (SSDs) are providing new ways for improving or replacing sensory abilities that have been lost due to disease or injury, and at the same time offer unprecedented opportunities to address how the nervous system could lead to an augmentation of its capacities. In this work we have evaluated a color-blind subject using a new visual-to-auditory SSD device called “Eyeborg”, that allows colors to be perceived as sounds. We used a combination of neuroimaging techniques including Functional Magnetic Resonance Imaging (fMRI), Diffusion Tensor Imaging (DTI) and proton Magnetic Resonance Spectroscopy (1H-MRS) to study potential brain plasticity in this subject. Our results suggest that after 8 years of continuous use of this device there could be significant adaptive and compensatory changes within the brain. In particular, we found changes in functional neural patterns, structural connectivity and cortical topography at the visual and auditive cortex of the Eyeborg user in comparison with a control population. Although at the moment we cannot claim that the continuous use of the Eyeborg is the only reason for these findings, our results may shed further light on potential brain changes associated with the use of other SSDs. This could help to better understand how the brain adapts to several pathologies and uncover adaptive resources such as cross-modal representations. We expect that the precise understanding of these changes will have clear implications for rehabilitative training, device development and for more efficient programs for people with disabilities. PMID:25926778

  10. Hearing colors: An example of Brain Plasticity

    Directory of Open Access Journals (Sweden)

    ARANTXA eALFARO

    2015-04-01

    Full Text Available Sensory substitution devices are providing new ways for improving or replacing sensory abilities that have been lost due to disease or injury, and at the same time offer unprecedented opportunities to address how the nervous system could lead to an augmentation of its capacities. In this work we have evaluated a color-blind subject using a new visual-to-auditory sensory substitution device (SSD device called Eyeborg, that allows colors to be perceived as sounds. We used a combination of neuroimaging techniques including Functional Magnetic Resonance Imaging (fMRI, Diffusion Tensor Imaging (DTI and proton Magnetic Resonance Spectroscopy (1H-MRS to study potential brain plasticity in this subject. Our results suggest that after 8 years of continuous use of this device there could be significant adaptive and compensatory changes within the brain. In particular, we found changes in functional neural patterns, structural connectivity and cortical topography at the visual and auditive cortex of the Eyeborg user in comparison with a control population. Although at the moment we cannot claim that the continuous use of the Eyeborg is the only reason for these findings, our results may shed further light on potential brain changes associated with the use of other SSDs. This could help to better understand how the brain adapts to several pathologies and uncover adaptive resources such as cross-modal representations. We expect that the precise understanding of these changes will have clear implications for rehabilitative training, device development and for more efficient programs for people with disabilities.

  11. Auditory complaints in scuba divers: an overview.

    Science.gov (United States)

    Evens, Rachel A; Bardsley, Barry; C Manchaiah, Vinaya K

    2012-03-01

    Pre-1970s, diving was seen as a predominantly male working occupation. Since then it has become a popular hobby, with increasing access to SCUBA diving while on holiday. For a leisure activity, diving puts the auditory system at the risk of a wide variety of complaints. However, there is still insufficient consensus on the frequency of these conditions, which ultimately would require more attention from hearing-healthcare professionals. A literature search of epidemiology studies of eight auditory complaints was conducted, using both individual and large-scale diving studies, with some reference to large-scale non-diving populations . A higher incidence was found for middle ear barotrauma, eustachian tube dysfunction, and alternobaric vertigo with a high correlation among females. Comparing these findings with a non-diving population found no statistically significant difference for hearing loss or tinnitus. Increased awareness of health professionals is required, training, and implementation of the Frenzel technique would help resolve the ambiguities of the Valsalva technique underwater. PMID:23448900

  12. Happiness increases distraction by auditory deviant stimuli.

    Science.gov (United States)

    Pacheco-Unguetti, Antonia Pilar; Parmentier, Fabrice B R

    2016-08-01

    Rare and unexpected changes (deviants) in an otherwise repeated stream of task-irrelevant auditory distractors (standards) capture attention and impair behavioural performance in an ongoing visual task. Recent evidence indicates that this effect is increased by sadness in a task involving neutral stimuli. We tested the hypothesis that such effect may not be limited to negative emotions but reflect a general depletion of attentional resources by examining whether a positive emotion (happiness) would increase deviance distraction too. Prior to performing an auditory-visual oddball task, happiness or a neutral mood was induced in participants by means of the exposure to music and the recollection of an autobiographical event. Results from the oddball task showed significantly larger deviance distraction following the induction of happiness. Interestingly, the small amount of distraction typically observed on the standard trial following a deviant trial (post-deviance distraction) was not increased by happiness. We speculate that happiness might interfere with the disengagement of attention from the deviant sound back towards the target stimulus (through the depletion of cognitive resources and/or mind wandering) but help subsequent cognitive control to recover from distraction. PMID:26302716

  13. Selective attention in an insect auditory neuron.

    Science.gov (United States)

    Pollack, G S

    1988-07-01

    Previous work (Pollack, 1986) showed that an identified auditory neuron of crickets, the omega neuron, selectively encodes the temporal structure of an ipsilateral sound stimulus when a contralateral stimulus is presented simultaneously, even though the contralateral stimulus is clearly encoded when it is presented alone. The present paper investigates the physiological basis for this selective response. The selectivity for the ipsilateral stimulus is a result of the apparent intensity difference of ipsi- and contralateral stimuli, which is imposed by auditory directionality; when simultaneous presentation of stimuli from the 2 sides is mimicked by presenting low- and high-intensity stimuli simultaneously from the ipsilateral side, the neuron responds selectively to the high-intensity stimulus, even though the low-intensity stimulus is effective when it is presented alone. The selective encoding of the more intense (= ipsilateral) stimulus is due to intensity-dependent inhibition, which is superimposed on the cell's excitatory response to sound. Because of the inhibition, the stimulus with lower intensity (i.e., the contralateral stimulus) is rendered subthreshold, while the stimulus with higher intensity (the ipsilateral stimulus) remains above threshold. Consequently, the temporal structure of the low-intensity stimulus is filtered out of the neuron's spike train. The source of the inhibition is not known. It is not a consequence of activation of the omega neuron. Its characteristics are not consistent with those of known inhibitory inputs to the omega neuron.

  14. Organization of the auditory brainstem in a lizard, Gekko gecko. I. Auditory nerve, cochlear nuclei, and superior olivary nuclei

    DEFF Research Database (Denmark)

    Tang, Y. Z.; Christensen-Dalsgaard, J.; Carr, C. E.

    2012-01-01

    We used tract tracing to reveal the connections of the auditory brainstem in the Tokay gecko (Gekko gecko). The auditory nerve has two divisions, a rostroventrally directed projection of mid- to high best-frequency fibers to the nucleus angularis (NA) and a more dorsal and caudal projection of low...

  15. Auditory Preferences of Young Children with and without Hearing Loss for Meaningful Auditory-Visual Compound Stimuli

    Science.gov (United States)

    Zupan, Barbra; Sussman, Joan E.

    2009-01-01

    Experiment 1 examined modality preferences in children and adults with normal hearing to combined auditory-visual stimuli. Experiment 2 compared modality preferences in children using cochlear implants participating in an auditory emphasized therapy approach to the children with normal hearing from Experiment 1. A second objective in both…

  16. Auditory Masking Effects on Speech Fluency in Apraxia of Speech and Aphasia: Comparison to Altered Auditory Feedback

    Science.gov (United States)

    Jacks, Adam; Haley, Katarina L.

    2015-01-01

    Purpose: To study the effects of masked auditory feedback (MAF) on speech fluency in adults with aphasia and/or apraxia of speech (APH/AOS). We hypothesized that adults with AOS would increase speech fluency when speaking with noise. Altered auditory feedback (AAF; i.e., delayed/frequency-shifted feedback) was included as a control condition not…

  17. Middle components of the auditory evoked response in bilateral temporal lobe lesions. Report on a patient with auditory agnosia

    DEFF Research Database (Denmark)

    Parving, A; Salomon, G; Elberling, Claus;

    1980-01-01

    An investigation of the middle components of the auditory evoked response (10--50 msec post-stimulus) in a patient with auditory agnosia is reported. Bilateral temporal lobe infarctions were proved by means of brain scintigraphy, CAT scanning, and regional cerebral blood flow measurements. The mi...

  18. How bees distinguish colors

    Directory of Open Access Journals (Sweden)

    Horridge A

    2015-03-01

    Full Text Available Adrian Horridge Biological Sciences, Australian National University, Canberra, ACT, Australia Abstract: Behind each facet of the compound eye, bees have photoreceptors for ultraviolet, green, and blue wavelengths that are excited by sunlight reflected from the surrounding panorama. In experiments that excluded ultraviolet, bees learned to distinguish between black, gray, white, and various colors. To distinguish two targets of differing color, bees detected, learned, and later recognized the strongest preferred inputs, irrespective of which target displayed them. First preference was the position and measure of blue reflected from white or colored areas. They also learned the positions and a measure of the green receptor modulation at vertical edges that displayed the strongest green contrast. Modulation is the receptor response to contrast and was summed over the length of a contrasting vertical edge. This also gave them a measure of angular width between outer vertical edges. Third preference was position and a measure of blue modulation. When they returned for more reward, bees recognized the familiar coincidence of these inputs at that place. They cared nothing for colors, layout of patterns, or direction of contrast, even at black/white edges. The mechanism is a new kind of color vision in which a large-field tonic blue input must coincide in time with small-field phasic modulations caused by scanning vertical edges displaying green or blue contrast. This is the kind of system to expect in medium-lowly vision, as found in insects; the next steps are fresh looks at old observations and quantitative models. Keywords: vision, honey bee, visual processing, optimum system, picture sorting

  19. Functional studies of the human auditory cortex, auditory memory and musical hallucinations

    International Nuclear Information System (INIS)

    Objectives. 1. To determine which areas of the cerebral cortex are activated stimulating the left ear with pure tones, and what type of stimulation occurs (eg. excitatory or inhibitory) in these different areas. 2. To use this information as an initial step to develop a normal functional data base for future studies. 3. To try to determine if there is a biological substrate to the process of recalling previous auditory perceptions and if possible, suggest a locus for auditory memory. Method. Brain perfusion single photon emission computerized tomography (SPECT) evaluation was conducted: 1-2) Using auditory stimulation with pure tones in 4 volunteers with normal hearing. 3) In a patient with bilateral profound hearing loss who had auditory perception of previous musical experiences; while injected with Tc99m HMPAO while she was having the sensation of hearing a well known melody. Results. Both in the patient with auditory hallucinations and the normal controls -stimulated with pure tones- there was a statistically significant increase in perfusion in Brodmann's area 39, more intense on the right side (right to left p < 0.05). With a lesser intensity there was activation in the adjacent area 40 and there was intense activation also in the executive frontal cortex areas 6, 8, 9, and 10 of Brodmann. There was also activation of area 7 of Brodmann; an audio-visual association area; more marked on the right side in the patient and the normal stimulated controls. In the subcortical structures there was also marked activation in the patient with hallucinations in both lentiform nuclei, thalamus and caudate nuclei also more intense in the right hemisphere, 5, 4.7 and 4.2 S.D. above the mean respectively and 5, 3.3, and 3 S.D. above the normal mean in the left hemisphere respectively. Similar findings were observed in normal controls. Conclusions. After auditory stimulation with pure tones in the left ear of normal female volunteers, there is bilateral activation of area 39

  20. Human preference for individual colors

    Science.gov (United States)

    Palmer, Stephen E.; Schloss, Karen B.

    2010-02-01

    Color preference is an important aspect of human behavior, but little is known about why people like some colors more than others. Recent results from the Berkeley Color Project (BCP) provide detailed measurements of preferences among 32 chromatic colors as well as other relevant aspects of color perception. We describe the fit of several color preference models, including ones based on cone outputs, color-emotion associations, and Palmer and Schloss's ecological valence theory. The ecological valence theory postulates that color serves an adaptive "steering' function, analogous to taste preferences, biasing organisms to approach advantageous objects and avoid disadvantageous ones. It predicts that people will tend to like colors to the extent that they like the objects that are characteristically that color, averaged over all such objects. The ecological valence theory predicts 80% of the variance in average color preference ratings from the Weighted Affective Valence Estimates (WAVEs) of correspondingly colored objects, much more variance than any of the other models. We also describe how hue preferences for single colors differ as a function of gender, expertise, culture, social institutions, and perceptual experience.

  1. A color management system for multi-colored LED lighting

    DEFF Research Database (Denmark)

    Chakrabarti, Maumita; Thorseth, Anders; Jepsen, Jørgen;

    2015-01-01

    A new color control system is described and implemented for a five–color LED light engine, covering a wide white gamut. The system combines a new way of using pre-calibrated look-up tables and a rule-based optimization of chromaticity distance from the Planckian locus with a calibrated color sens...

  2. Randomized $\\Delta$-Edge-Coloring via Quaternion of Complex Colors

    CERN Document Server

    Lee, Tony T; Guan, Hao

    2011-01-01

    This paper explores the application of a new algebraic method of color exchanges to the edge coloring of simple graphs. Vizing's theorem states that the edge coloring of a simple graph $G$ requires either $\\Delta$ or $\\Delta+1$ colors, where $\\Delta$ is the maximum vertex degree of $G$. Holyer proved that it is {\\bf NP}-complete to decide whether $G$ is $\\Delta$-edge-colorable even for cubic graphs. By introducing the concept of complex colors, we show that the color-exchange operation follows the same multiplication rules as quaternion. An initially $\\Delta$-edge-colored graph $G$ allows variable-colored edges, which can be eliminated by color exchanges in a manner similar to variable eliminations in solving systems of linear equations. The problem is solved if all variables are eliminated and a properly $\\Delta$-edge-colored graph is reached. For a randomly generated graph $G$, we prove that our algorithm returns a proper $\\Delta$-edge-coloring with a probability of at least 1/2 in $O(\\Delta|V||E|^5)$ time ...

  3. Testing Children for Color Blindness

    Science.gov (United States)

    ... Español Eye Health / News Testing Children for Color Blindness Written by: Shirley Dang Apr. 03, 2014 New ... shows that kids can be tested for color blindness as soon as age 4, finds Caucasian boys ...

  4. Color Changes Mark Polymer Reactions.

    Science.gov (United States)

    Krieger, James H.

    1980-01-01

    Describes how polydiacetylenes can be used as educational aids. These polymers have conjugated backbones, which cause changes in color when the polydiacetylenes undergo various chemical and physical processes. Diagrams summarize all chemical reactions and their associated color changes. (CS)

  5. Personalized 2D color maps

    KAUST Repository

    Waldin, Nicholas

    2016-06-24

    2D color maps are often used to visually encode complex data characteristics such as heat or height. The comprehension of color maps in visualization is affected by the display (e.g., a monitor) and the perceptual abilities of the viewer. In this paper we present a novel method to measure a user\\'s ability to distinguish colors of a two-dimensional color map on a given monitor. We show how to adapt the color map to the user and display to optimally compensate for the measured deficiencies. Furthermore, we improve user acceptance of the calibration procedure by transforming the calibration into a game. The user has to sort colors along a line in a 3D color space in a competitive fashion. The errors the user makes in sorting these lines are used to adapt the color map to his perceptual capabilities.

  6. Identity Based Color Image Cryptography

    OpenAIRE

    Gopi Krishnan S; Loganathan D

    2011-01-01

    An Identity based cryptography based on visual cryptography scheme was proposed for protecting color image. A color image to be protected and authentic entities such as account number, password, signature image are given as input. The binary key image is obtained by distributing the digital signature of obtained authentic entities. A secret color image which needs to be communicated is decomposed into three grayscale tones of Y-Cb-Cr color component. Then these grayscale images are half-toned...

  7. Color correction using color-flow eigenspace model in color face recognition

    Science.gov (United States)

    Choi, JaeYoung; Ro, Yong Man

    2009-02-01

    We propose a new color correction approach which, as opposed to existing methods, take advantages of a given pair of two color face images (probe and gallery) in the color face recognition (FR) framework. In the proposed color correction method, the color-flow vector and color-flow eigenspace model are developed to generate color corrected probe images. The main contribution of this paper is threefold: 1) the proposed method can reliably compensate the non-linear photic variations imposed on probe face images comparing to traditional color correction techniques; 2) to the best of our knowledge, for the first time, we conduct extensive experiment studies to compare the effectiveness of various color correction methods to deal with photometrical distortions in probe images; 3) the proposed method can significantly enhance the recognition performance degraded by severely illuminant probe face images. Two standard face databases CMU PIE and XM2VTSDB were used to demonstrate the effectiveness of the proposed color correction method. The usefulness of the proposed method in the color FR is shown in terms of both absolute and comparative recognition performances against four traditional color correction solutions of White balance, Gray-world, Retinex, and Color-by-correlation.

  8. Progress in color night vision

    NARCIS (Netherlands)

    Toet, A.; Hogervorst, M.A.

    2012-01-01

    We present an overview of our recent progress and the current state-of-the-art techniques of color image fusion for night vision applications. Inspired by previously developed color opponent fusing schemes, we initially developed a simple pixel-based false color-mapping scheme that yielded fused fal

  9. Astronomy with the Color Blind

    Science.gov (United States)

    Smith, Donald A.; Melrose, Justyn

    2014-01-01

    The standard method to create dramatic color images in astrophotography is to record multiple black and white images, each with a different color filter in the optical path, and then tint each frame with a color appropriate to the corresponding filter. When combined, the resulting image conveys information about the sources of emission in the…

  10. Can Coloring Mandalas Reduce Anxiety?

    Science.gov (United States)

    Curry, Nancy A.; Kasser, Tim

    2005-01-01

    This study examined the effectiveness of different types of art activities in the reduction of anxiety. After undergoing a brief anxiety-induction, 84 undergraduate students were randomly assigned to color a mandala, to color a plaid form, or to color on a blank piece of paper. Results demonstrated that anxiety levels declined approximately the…

  11. Color Addition and Subtraction Apps

    Science.gov (United States)

    Ruiz, Frances; Ruiz, Michael J.

    2015-01-01

    Color addition and subtraction apps in HTML5 have been developed for students as an online hands-on experience so that they can more easily master principles introduced through traditional classroom demonstrations. The evolution of the additive RGB color model is traced through the early IBM color adapters so that students can proceed step by step…

  12. Violating expectations of color order

    Science.gov (United States)

    Burling, Bil; Bender, Walter R.

    1996-04-01

    An exploration of emotion in color communication is presented in this paper. It begins with an outline of a proposed theory of emotion and a hypothesis of how color may induce emotion. A discussion follows that details what is essential in a color message to predict emotional responses. Experiments are described that might assist in validating the theory put forth in this paper.

  13. Image composition with color harmonization

    Institute of Scientific and Technical Information of China (English)

    Congde Wang; Rong Zhang; Fan Deng

    2009-01-01

    Image matting and color transfer are combined to achieve image composition.Firstly,digital matting is used to pull out the region of interest.Secondly,taking color harmonization into account,color transfer techniques are introduced in pasting the region onto the target image.Experimental results show that the proposed approach generates visually plea.sing composite images.

  14. Auditory-perceptual learning improves speech motor adaptation in children.

    Science.gov (United States)

    Shiller, Douglas M; Rochon, Marie-Lyne

    2014-08-01

    Auditory feedback plays an important role in children's speech development by providing the child with information about speech outcomes that is used to learn and fine-tune speech motor plans. The use of auditory feedback in speech motor learning has been extensively studied in adults by examining oral motor responses to manipulations of auditory feedback during speech production. Children are also capable of adapting speech motor patterns to perceived changes in auditory feedback; however, it is not known whether their capacity for motor learning is limited by immature auditory-perceptual abilities. Here, the link between speech perceptual ability and the capacity for motor learning was explored in two groups of 5- to 7-year-old children who underwent a period of auditory perceptual training followed by tests of speech motor adaptation to altered auditory feedback. One group received perceptual training on a speech acoustic property relevant to the motor task while a control group received perceptual training on an irrelevant speech contrast. Learned perceptual improvements led to an enhancement in speech motor adaptation (proportional to the perceptual change) only for the experimental group. The results indicate that children's ability to perceive relevant speech acoustic properties has a direct influence on their capacity for sensory-based speech motor adaptation.

  15. Functional sex differences in human primary auditory cortex

    Energy Technology Data Exchange (ETDEWEB)

    Ruytjens, Liesbet [University Medical Center Groningen, Department of Otorhinolaryngology, Groningen (Netherlands); University Medical Center Utrecht, Department Otorhinolaryngology, P.O. Box 85500, Utrecht (Netherlands); Georgiadis, Janniko R. [University of Groningen, University Medical Center Groningen, Department of Anatomy and Embryology, Groningen (Netherlands); Holstege, Gert [University of Groningen, University Medical Center Groningen, Center for Uroneurology, Groningen (Netherlands); Wit, Hero P. [University Medical Center Groningen, Department of Otorhinolaryngology, Groningen (Netherlands); Albers, Frans W.J. [University Medical Center Utrecht, Department Otorhinolaryngology, P.O. Box 85500, Utrecht (Netherlands); Willemsen, Antoon T.M. [University Medical Center Groningen, Department of Nuclear Medicine and Molecular Imaging, Groningen (Netherlands)

    2007-12-15

    We used PET to study cortical activation during auditory stimulation and found sex differences in the human primary auditory cortex (PAC). Regional cerebral blood flow (rCBF) was measured in 10 male and 10 female volunteers while listening to sounds (music or white noise) and during a baseline (no auditory stimulation). We found a sex difference in activation of the left and right PAC when comparing music to noise. The PAC was more activated by music than by noise in both men and women. But this difference between the two stimuli was significantly higher in men than in women. To investigate whether this difference could be attributed to either music or noise, we compared both stimuli with the baseline and revealed that noise gave a significantly higher activation in the female PAC than in the male PAC. Moreover, the male group showed a deactivation in the right prefrontal cortex when comparing noise to the baseline, which was not present in the female group. Interestingly, the auditory and prefrontal regions are anatomically and functionally linked and the prefrontal cortex is known to be engaged in auditory tasks that involve sustained or selective auditory attention. Thus we hypothesize that differences in attention result in a different deactivation of the right prefrontal cortex, which in turn modulates the activation of the PAC and thus explains the sex differences found in the activation of the PAC. Our results suggest that sex is an important factor in auditory brain studies. (orig.)

  16. Functional sex differences in human primary auditory cortex

    International Nuclear Information System (INIS)

    We used PET to study cortical activation during auditory stimulation and found sex differences in the human primary auditory cortex (PAC). Regional cerebral blood flow (rCBF) was measured in 10 male and 10 female volunteers while listening to sounds (music or white noise) and during a baseline (no auditory stimulation). We found a sex difference in activation of the left and right PAC when comparing music to noise. The PAC was more activated by music than by noise in both men and women. But this difference between the two stimuli was significantly higher in men than in women. To investigate whether this difference could be attributed to either music or noise, we compared both stimuli with the baseline and revealed that noise gave a significantly higher activation in the female PAC than in the male PAC. Moreover, the male group showed a deactivation in the right prefrontal cortex when comparing noise to the baseline, which was not present in the female group. Interestingly, the auditory and prefrontal regions are anatomically and functionally linked and the prefrontal cortex is known to be engaged in auditory tasks that involve sustained or selective auditory attention. Thus we hypothesize that differences in attention result in a different deactivation of the right prefrontal cortex, which in turn modulates the activation of the PAC and thus explains the sex differences found in the activation of the PAC. Our results suggest that sex is an important factor in auditory brain studies. (orig.)

  17. A corollary discharge maintains auditory sensitivity during sound production.

    Science.gov (United States)

    Poulet, James F A; Hedwig, Berthold

    2002-08-22

    Speaking and singing present the auditory system of the caller with two fundamental problems: discriminating between self-generated and external auditory signals and preventing desensitization. In humans and many other vertebrates, auditory neurons in the brain are inhibited during vocalization but little is known about the nature of the inhibition. Here we show, using intracellular recordings of auditory neurons in the singing cricket, that presynaptic inhibition of auditory afferents and postsynaptic inhibition of an identified auditory interneuron occur in phase with the song pattern. Presynaptic and postsynaptic inhibition persist in a fictively singing, isolated cricket central nervous system and are therefore the result of a corollary discharge from the singing motor network. Mimicking inhibition in the interneuron by injecting hyperpolarizing current suppresses its spiking response to a 100-dB sound pressure level (SPL) acoustic stimulus and maintains its response to subsequent, quieter stimuli. Inhibition by the corollary discharge reduces the neural response to self-generated sound and protects the cricket's auditory pathway from self-induced desensitization.

  18. Biological impact of music and software-based auditory training

    Science.gov (United States)

    Kraus, Nina

    2012-01-01

    Auditory-based communication skills are developed at a young age and are maintained throughout our lives. However, some individuals – both young and old – encounter difficulties in achieving or maintaining communication proficiency. Biological signals arising from hearing sounds relate to real-life communication skills such as listening to speech in noisy environments and reading, pointing to an intersection between hearing and cognition. Musical experience, amplification, and software-based training can improve these biological signals. These findings of biological plasticity, in a variety of subject populations, relate to attention and auditory memory, and represent an integrated auditory system influenced by both sensation and cognition. Learning outcomes The reader will (1) understand that the auditory system is malleable to experience and training, (2) learn the ingredients necessary for auditory learning to successfully be applied to communication, (3) learn that the auditory brainstem response to complex sounds (cABR) is a window into the integrated auditory system, and (4) see examples of how cABR can be used to track the outcome of experience and training. PMID:22789822

  19. 'Fram' in Color

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Click on the image for 'Fram' in Color (QTVR) This view in approximately true color reveals details in an impact crater informally named 'Fram' in the Meridian Planum region of Mars. The picture is a mosaic of frames taken by the panoramic camera on NASA's Mars Exploration Rover Opportunity during the rover's 88th martian day on Mars, on April 23, 2004. The crater spans about 8 meters (26 feet) in diameter. Opportunity paused beside it while traveling from the rover's landing site toward a larger crater farther east. This view combines images taken using three of the camera's filters for different wavelengths of light: 750 nanometers, 530 nanometers and 430 nanometers.

  20. RGBW color separation for field sequential color LCDs

    Science.gov (United States)

    Sun, Pei-Li

    2008-01-01

    Field sequential color (FSC) LCD is one of the preferred display technologies to achieve wide color gamut and high luminous efficiency. But this technology suffers from an unpleasing color breakup effect. This phenomenon can be reduced by adding a white primary. As RGBW primaries are recommended for FSC-LCD, the next question is how to convert standard RGB signals to RGBW without large color variations. The present study first optimal the spectra of RGB primaries using the 3D gamut boundaries of standard object color spectra (SOCS) database and Adobe RGB in CIECAM02 space with observer metamerism constraint. The optimal RGB primaries then were used to derive six modes for RGB to RGBW conversion. The final step is to further optimize color correction matrix based on CIE170-1:2006 'age and size dependent cone fundamentals' to compensate the visual color shift of elders.